G1831 001 Cameby Downs GIA V01.01 Draft

Cameby Downs Continued Operations Project

EnvironmentalEnvironmental Values Assessment Assessment

APPENDIX C

Groundwater Assessment Report on Cameby Downs Continued Operations Project Groundwater Impact Assessment

Prepared for Syntech Resources Pty Ltd

Project No. G1831 September 2018 www.ageconsultants.com.au ABN 64 080 238 642

Document details and history

Document details

Project number G1831 Document title Cameby Downs Continued Operations Project – Groundwater Impact Assessment Site address Cameby Downs Mine, Warrego Highway, Miles File name G1831_001_Cameby Downs GIA_v05.03a.docx

Document status and review

Authorised Edition Comments Author Date by

v05.03a Final report with minor updates addressing DES comments DWI/AMD/JB JST 07/09/2018

This document is and remains the property of AGE, and may only be used for the purpose for which it was commissioned and in accordance with the Terms of Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited.

Australasian Groundwater and Environmental Consultants Pty Ltd

AGE Head Office AGE Newcastle Office AGE Townsville Office Level 2 / 15 Mallon Street, 4 Hudson Street Unit 3, Building A, 10 Cummins Street Bowen Hills, QLD 4006, Australia Hamilton, NSW 2303, Australia Hyde Park, QLD 4812, Australia T. +61 7 3257 2055 T. +61 2 4962 2091 T. +61 7 4413 2020 F. +61 7 3257 2088 F. +61 2 4962 2096 F. +61 7 3257 2088 brisbane@ageconsultants.com.au [email protected] [email protected]

Table of contents

Page No.

1 Introduction ...... 1 1.1 Project description ...... 3 1.1.1 Approved Cameby Downs Mine ...... 3 1.1.2 Proposed project ...... 3 1.2 Background to assessment ...... 6 1.3 Scope of assessment ...... 6 2 Regulatory framework...... 8 2.1 Commonwealth Environment Protection and Biodiversity Conservation Act 1999 ...... 8 2.2 Queensland regulatory framework ...... 8 2.2.1 Environmental Protection (Water) Policy 2009 ...... 9 2.2.2 Water Plan (Great Artesian Basin and Other Regional Aquifers) 2017 ...... 9 2.2.3 Declared Sub-Artesian areas ...... 11 2.2.4 Water Resource (Condamine and Balonne) Plan 2004 ...... 11 2.3 Groundwater licensing for the project ...... 11 3 Environmental setting ...... 12 3.1 Terrain and drainage ...... 12 3.2 Land use ...... 12 3.3 Climate ...... 14 4 Groundwater monitoring network ...... 16 5 Geological setting ...... 20 5.1 Regional geology...... 20 5.2 Geology of the Project area ...... 23 5.2.1 Walloon Coal Measures ...... 23 5.2.2 Springbok Sandstone ...... 26 5.2.3 Tertiary sediments ...... 26 5.2.4 Quaternary sediments ...... 26 5.3 Structural geology ...... 26 6 Hydrogeology ...... 27 6.1 Quaternary sediments ...... 27 6.2 Tertiary sediments ...... 28 6.3 Springbok Sandstone ...... 28 6.4 Walloon Coal Measures ...... 30 6.5 Hydraulic parameters ...... 30 6.6 Existing data and monitoring ...... 31 6.7 Groundwater quality...... 34 6.7.1 Geochemistry ...... 35 6.8 Groundwater recharge, distribution and flow ...... 36 6.9 Groundwater use ...... 36 6.9.1 Approved Cameby Downs Mine ...... 36

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6.9.2 Coal seam gas ...... 37 6.9.3 Registered groundwater users ...... 37 6.10 Groundwater dependent ecosystems ...... 39 7 Conceptual groundwater model ...... 42 8 Environmental value of groundwater ...... 44 8.1 Aquatic ecosystem ...... 44 8.2 Aquaculture and aquatic foods for human consumption ...... 44 8.3 Agricultural purposes ...... 45 8.4 Recreation ...... 46 8.5 Drinking water ...... 46 8.6 Industrial purposes ...... 46 8.7 Cultural and spiritual values ...... 46 8.8 Conclusion ...... 46 9 Impact assessment ...... 47 9.1 Introduction ...... 47 9.2 Summary of approved mining impacts for the Cameby Downs Mine ...... 47 9.3 Overview of groundwater modelling for the Project ...... 53 9.3.1 Proposed mine plan ...... 53 9.4 Groundwater modelling predictions ...... 55 9.4.1 Groundwater inflow to mining areas ...... 55 9.4.2 Drawdown and depressurisation during mining operations ...... 59 9.4.3 Cumulative impacts...... 64 9.4.4 Water licensing ...... 67 9.4.5 Impacts on groundwater users ...... 67 9.4.6 Impacts on groundwater dependent ecosystems ...... 69 9.4.7 Impacts on environmental values ...... 69 9.5 Post mining recovery conditions ...... 69 9.5.1 Post closure groundwater recovery...... 70 9.5.2 Jurassic groundwater intercepted post mining ...... 73 9.6 Impacts on groundwater quality ...... 73 9.6.1 Overburden emplacement areas and final void lakes ...... 73 9.6.2 Hydrocarbons...... 73 9.6.3 Coal rejects storage ...... 73 10 EPBC Act Significant Impact on Water Resources Guidelines ...... 75 10.1 Water availability to users ...... 75 10.2 Water availability to the environment ...... 75 10.3 Water quality ...... 75 10.4 Cumulative impacts ...... 76 10.5 Avoidance or mitigation measures ...... 76 10.6 Conclusion ...... 77

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11 Groundwater monitoring strategy / program ...... 78 11.1 Monitoring bore network ...... 78 11.2 Water level monitoring plan ...... 82 11.3 Water quality monitoring plan ...... 82 11.4 Groundwater triggers ...... 82 11.4.1 Groundwater level trigger thresholds ...... 82 11.4.2 Groundwater quality trigger values ...... 83 11.5 Mine groundwater inflow monitoring ...... 85 11.6 Data management and reporting ...... 86 12 Conclusions ...... 87 13 References...... 88

List of figures Figure 1.1 Project location ...... 2 Figure 1.2 Project layout ...... 5 Figure 2.1 Groundwater management areas ...... 10 Figure 3.1 Terrain and land use ...... 13 Figure 3.2 Cumulative rainfall departure ...... 15 Figure 4.1 Cameby Downs groundwater monitoring network ...... 17 Figure 5.1 Surface geology ...... 22 Figure 5.2 Coal seams within the Juandah Coal Measures (source: Syntech Resources, 2016) ...... 24 Figure 5.3 KG1 Seam overburden thickness and WM3 Seam floor structure ...... 25 Figure 6.1 GAB recharge beds ...... 29 Figure 6.2 Groundwater level hydrographs ...... 31 Figure 6.3 Groundwater level contours - MA1 / MA2 coal seams ...... 33 Figure 6.4 Piper diagram ...... 35 Figure 6.5 Groundwater users surrounding the Project area ...... 38 Figure 6.6 Potential groundwater dependent ecosystems (GDE Atlas) ...... 40 Figure 7.1 Schematic showing conceptual groundwater model ...... 43 Figure 9.1 Approved drawdown extent in Walloon Coal Measures – end of mining (AGE, 2006) .. 49 Figure 9.2 Approved drawdown extent in Walloon Coal Measures – 100 years post mining (AGE, 2006) ...... 50 Figure 9.3 Predicted drawdown extent for 2015 (AGE, 2015) ...... 52 Figure 9.4 Proposed continued operations project mine plan...... 54 Figure 9.5 Predicted average annual pit inflows ...... 55 Figure 9.6 Kumbarilla Beds (Layer 1) - Maximum zone of drawdown (proposed Extension only) 60

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Figure 9.7 Walloon Coal Measures (Layer 2) – Maximum zone of drawdown (Proposed Extension only) ...... 61 Figure 9.8 Kumbarilla Beds (Layer 1) – Maximum zone of drawdown (Approved and Proposed Extension mine plans) ...... 62 Figure 9.9 Walloon Coal Measures (Layer 2) – Maximum zone of drawdown (Approved and Proposed Extension mine plans) ...... 63 Figure 9.10 Maximum cumulative drawdown (CSG Extraction, Approved and Proposed mine plan) – Kumbarilla Beds (Layer 1) ...... 65 Figure 9.11 Maximum cumulative drawdown (CSG Extraction, Approved and Proposed mine plan) – Walloon Coal Measures (Layer 2) ...... 66 Figure 9.12 Landholder bores within predicted maximum zone of drawdown during mining ...... 68 Figure 9.13 Post mining equilibrium – drawdown and potentiometric surface – Kumbarilla Beds (Layer 1) ...... 71 Figure 9.14 Post mining equilibrium – drawdown and potentiometric surface – Walloon Coal Measures (Layer 2) ...... 72 Figure 11.1 Proposed Cameby Downs groundwater monitoring network ...... 81

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List of tables Table 3.1 Climate data ...... 14 Table 4.1 Monitoring bore summary ...... 18 Table 4.2 Additional OGIA monitoring bore summary ...... 19 Table 5.1 Surat Basin stratigraphy – northeastern area ...... 21 Table 6.1 Groundwater characteristics of geological units within the Project area ...... 27 Table 6.2 Hydraulic testing results of the MA1 / MA2 coal seams ...... 30 Table 6.3 Additional site groundwater level data (June 2017) ...... 32 Table 6.4 Groundwater quality for the MA1 / MA2 coal seams ...... 34 Table 8.1 Tolerance of livestock (beef cattle) to TDS in drinking water ...... 45 Table 8.2 Livestock (cattle) drinking guidelines (ANZECC, 2000) ...... 45 Table 9.1 Predicted groundwater extraction – 2018 to 2090 ...... 56 Table 11.1 Proposed Cameby Downs monitoring network ...... 79 Table 11.2 Groundwater level trigger thresholds ...... 83 Table 11.3 Comparison of Cameby Downs Mine groundwater quality data and ecosystem trigger values ...... 84 Table 11.4 Proposed Cameby Downs Mine groundwater quality trigger values ...... 85

List of appendices Appendix A IESC Guidelines Appendix B Cameby Downs Mine – Water Quality Data, April 2009 to January 2016 Appendix C Summary of DNRME registered bores within a 10 km buffer zone Appendix D Bore census (October 2017) Appendix E Cameby Downs Continued Operations Project – Numerical Modelling Report

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Report on Cameby Downs Continued Operations Project Groundwater Impact Assessment

1 Introduction

Syntech Resources Pty Ltd (Syntech Resources) has lodged an amendment application to the Cameby Downs Mine Environmental Authority (EA) EPML00900113 in accordance with Section 224 of the Queensland Environmental Protection Act 1994 (EP Act) to approve the Cameby Downs Mine Continued Operations Project (the Project).

The Cameby Downs Mine is located approximately 360 kilometres (km) west-north-west of Brisbane in the Western Downs Regional Council (WDRC) local government area. The regional location of the Project is shown on Figure 1.1.

The Project involves the extension of operations within Mining Lease (ML) 50233, and into Mining Lease Applications (MLAs) 50258, 50259, 50260 and 50269 (Project area), and an increase in the run-of-mine (ROM) coal mining rate from the currently approved 2.8 million tonnes per annum (Mtpa) to 3.5 Mtpa.

Syntech Resources is seeking approval of the Project through a major amendment of the EA in accordance with Chapter 5, Part 7, Section 224 of the EP Act. The EA amendment application was lodged with then Department of Environment and Heritage Protection (DEHP), now named (and referred hereafter) as the Department of Environment and Science (DES) on 21 November 2016. DES subsequently made its Assessment Level Decision on 30 November 2016 that the proposed amendment is a major EA amendment application. DES issued an Information Request on 12 January 2017 to request additional information from Syntech Resources to enable them to make a decision on the application.

The Project will also be referred to the Commonwealth Minister for the Environment for consideration as to whether it constitutes a ‘controlled action’ and therefore may require approval under the Environment Protection and Biodiversity Conservation Act 1999 (Cwlth) (EPBC Act). The Independent Expert Scientific Committee (IESC) provides scientific advice to decision makers on the impact that coal seam gas and large coal mining development may have on water resources.

Australasian Groundwater and Environmental Consultants Pty Ltd (AGE) was engaged by Syntech Resources to develop a groundwater impact assessment (GIA) as part of the EA amendment application.

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1.1 Project description

This groundwater assessment examines the groundwater related impacts associated with the Project and compares those to the approved development, as well as the cumulative groundwater impacts from other resource developments.

1.1.1 Approved Cameby Downs Mine

The Cameby Downs Mine has been operating for approximately six years, with excavation of overburden commencing in July 2010 and first coal excavated in August 2010. The coal handling and preparation plant (CHPP) was commissioned in November 2010, with the first railing of coal occurring in December 2010.

The Cameby Downs Mine operates under EA EPML00900113 and involves operation of an open cut coal mine, CHPP and rail load-out infrastructure. The mine is currently approved to extract up to 2.8 Mtpa ROM coal over a mine life of approximately 45 years. After processing, the volume of product (thermal) coal is approximately 2.2 Mtpa. Product coal is loaded onto trains within ML 50233, and transported to the Port of Brisbane.

The region is a target area for coal seam gas (CSG), with numerous operations in existence or under application, including the development of a number of CSG wells within and surrounding ML 50233. Development of related infrastructure such as the Surat to Gladstone Pipeline (Surat Gladstone Pipeline Pty Ltd) has been approved.

1.1.2 Proposed project

Major elements of the Project relevant to the GIA include:  extension of open cut mining operations at an increased mining rate of 3.5 Mtpa ROM coal within ML 50233 and into MLAs 50258, 50259, 50260 and 50269;  upgrade and use of CHPP and general coal handling and rail loading facilities and other existing and approved supporting mine infrastructure;  the disposal of waste rock, comprising of overburden and interburden, in-pit or in out-of-pit waste rock emplacements;  the disposal of coal rejects in dedicated in-pit and out-of-pit rejects emplacements;  construction and operation of new ancillary infrastructure in support of mining operations including: satellite mine service and infrastructure areas, haul and access roads, workshop, diesel storage tanks, electricity supply and communications infrastructure and water management infrastructure;  increase in the life of the Cameby Downs Mine from 45 years to 75 years;  ongoing exploration activities within ML 50233 and MLAs 50258, 50259, 50260 and 50269;  progressive rehabilitation, as well as ultimate rehabilitation of the entire Project area once the site has been decommissioned; and  other associated minor infrastructure, plant and activities, where required.

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The approximate extents of the Project open cut mining components (including open cut pits, waste rock emplacements, out-of-pit rejects emplacements and final voids) are shown on Figure 1.2.

Mining to date has included open cut techniques targeting the coal seams of the Juandah Coal Measures. The Project includes continuation of open cut mining of the Juandah Coal Measures to an approximate depth of 40 m to 110 m below natural surface. The Kogan Seams, Macalister Coal Interval and lower Wambo Coal Intervals (that comprise the Juandah Coal Measures) will be targeted using excavators and trucked to the ROM coal stockpiles. The placement of waste rock includes both out-of-pit and in-pit emplacement.

Petroleum tenements overlap the Project area with co-development agreements in place and executed with BG International Pty Ltd and QGC (Shell). Agreements are to be developed with Arrow Energy in respect of the overlap within MLA 50258 and ML 50233. QGC has developed 25 CSG wells within ML 50233.

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | 4 RP187207 87 2 35 000 E EPC 813 - SE QLD COAL PTY LTD 1 RP187208 2 40 000\ SYNTECH RESOURCES PTY LTD BWR294 25 RP187207 MDL\ 43 EPC 732 - SYNTECH RESOURCES PTY LTD 3 CamebySE\ QLD\ COAL\ Downs PTY\ Continued Operations Project 24 RP187207 26 RP187208 2 RP187208 RP187208 86 23 FIGURE BWR294 RP187207 Project General Arrangement 4 28 1.2 KERWICKS ROAD 21\ \ RP1872 RP187208 BWR178 22 5 RP187208 Design Scale 20\ \ RP1872 RP187207 Drawn P Stewar 24.04.2018 Cad File Rev 2.0 6 RP187208 25 MLA 50259 BWR178 7 RP187208 BOORT-KOI\ ROA 88 18\ \ RP1872 19 9 8 RP187208 26 EPC 1041 - SE QLD COAL R E F E R E N C E BWR294 RP187207 RP187208 BWR178 17\ \ RP1872 Mining Lease

000 N Mining Lease Application 000 N 55 10 RP187208 Mineral Development Licence 55 70 70 27 15\ \ RP1872 16 Exploration Permit Coal BWR178 RP187207 11 RP187208 14\ \ RP1872 Indicative Extent of Additional 12 RP187208 Surface Development 24 ML 50233 240 Topography (RLm) AHD - 2mBWR178 Contours 13 RP187208 34 Existing Powerline TENNYSONS ROAD BWR487 74 Realigned Powerline BWR294 Mining Activity Final in Pit Spoil (Approximate Extent) 73 5 72 BWR294 1 RP893208 Waste Rock and Water Management BWR159 RP893208 Infrastructure (Approximate Extents) Final Void (Approximate Extents Out of Pit Rejects (Approximate Extent) Infrastructure15 14 CreekBWR178 Diversion (Approximate Alignment) BWR178 15 Existing/Approved Extent of Operations MLA 50258 BWR178 16 BWR151 4 RP893208 70 BWR159 DAVIES ROAD

KERWICKS ROAD GRAHAMS ROAD

ISONS ROAD 71 BWR159 2 RP893208

12 3 BWR149 RP893208

000 N 671 000 N 13 MDL 437 50 50 RP897022 BOORT-KOI\ ROA BWR149 70 EPC 81 70 11 68 BWR149 BWR 66 179 BWR154 DAVIES ROAD 65 RYALLS ROAD BWR154 MLA 50260 BOORT-KOI ROAD 672 Scale 1 : 60 000 RP897022 4 0 400 800 1200 1600 2000m 65 BWR154 BWR149

5 64 BWR149 BWR154 MLA 50269 64 MGA94 Z56 BWR154 96 BWR154 2 33 Water Pipeline BWR149 BWR149

To To QGC' Glen Eden Po 2 35 000 E 2 40 000 E

Project layout (source: Syntech Resources 2018) Figure 1.2 Groundwater Impact Assessment - Cameby Downs (G1831)

1.2 Background to assessment

AGE has carried out approvals and compliance assessments at Cameby Downs since 2004. This has included the following major investigations:  In 2004, AGE commenced work on Cameby Downs, then a greenfield project. Using geology, stratigraphy, exploration drill hole data and monitoring bores installed at the site, a conceptual hydrogeological model of the area was developed. Numerical groundwater modelling using FEFLOW was undertaken to assess the impact of the proposal on the groundwater resources and existing groundwater users. The groundwater recovery in the final void was simulated post mining and a groundwater monitoring program was designed on the basis of results of the GIA. The work was carried out for the proponent and the assessment was used to support the approvals process for the mine. A draft report was prepared in 2004 and finalised in 2006 (AGE, 2006).  In 2009/10, AGE was further involved at Cameby Downs to assess the impacts of an expansion to activities at the mine. The conceptualisation presented in the AGE (2006) assessment was used as the basis for the 2009/10 investigation. However, the impact assessment was updated through the development of a MODFLOW SURFACT numerical model. The work was undertaken as part of the Environmental Impact Assessment to obtain project approval. The work was completed for AARC on behalf of the proponent (AGE, 2010). This application was subsequently withdrawn and did not proceed.  In 2012/13, the above 2009/10 assessment was amended by AGE to address a change in mine plan. New predictions were carried out on the MODFLOW SURFACT model to simulate proposed mining under the amended project configuration. Once again the work was completed for AARC on behalf of the proponent (AGE, 2013), and the application was also subsequently withdrawn and did not proceed.  In 2015, AGE undertook an assessment for Syntech Resources to address conditions in EA EPML00900113. As per the EA EPML00900113 conditions, every five years Syntech Resources is required to assess groundwater monitoring data and use this data to validate the groundwater model. AGE re-ran the MODFLOW SURFACT model with the actual mined pit and schedule and assessed the water levels / drawdown at the groundwater monitoring sites. The intent was to determine if the model remained valid and simulates the inflows and drawdown that have been measured in the bores at the site (AGE, 2015).

1.3 Scope of assessment

The objectives of the GIA are to address the requirements of Commonwealth and Queensland government policy and to address the Project requirements. The scope of work for this groundwater assessment includes: 1. undertaking numerical groundwater modelling to predict the groundwater impact of the Project; and 2. preparing a contemporary groundwater report by: a) refining and updating the historic assessments and description of the conceptual groundwater regime to incorporate latest information and the Project; and b) reporting on the predicted impacts of the Project based upon the groundwater modelling outcomes.

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The existing model, which was initially developed in 2004, and subsequently updated in 2010 to reflect a revised mining plan, site data, and nearby CSG activity, has been used for this GIA. Given the model has previously been verified to historical data, the groundwater quality in the region is poor and there are few users of the system, the current model and impact assessment strategy are considered adequate in addressing the assessment requirements. The available data, conceptual understanding of the area and existing numerical model set-up is considered adequate and sufficient to develop a conservative model for predicting Project impacts. Based on this approach, the scope of work for this groundwater assessment includes:  updating historical groundwater and environmental assessments and geological and hydrogeological setting of the Project;  reviewing relevant exploration bore data;  reviewing hydrogeological data held on the Department of Natural Resources, Mines and Energy (DNRME) groundwater database (GWDB) for existing groundwater bores;  undertaking a bore census to update the previous bore census review undertaken in 2010;  analysis of all data and conceptualising the groundwater regime of the Project area;  updating the existing numerical model with the revised mine plan and also including nearby CSG activity to predict the cumulative impacts to the groundwater system;  rerunning the existing numerical model and undertake predictive modelling of the scale and extent of impacts upon groundwater levels, groundwater quality and groundwater users at various stages of proposed mine operations and post closure;  predictive modelling of the scale and extent of the cumulative impacts of the proposed mine operations from that approved for the existing mine operations and adjacent CSG activities for the proposed mine operations and post closure;  assessing groundwater impacts and developing feasible mitigation and management strategies where potential adverse impacts are identified; and  revising and updating the groundwater monitoring program.

The assessment of groundwater dependent ecosystems (GDEs) and stygofauna within the Project area and its surrounds are discussed further in Section 6.10.

This report presents an assessment of depressurisation effects arising from the Project for both the current approved and proposed mine plans and operations. A numerical model has been developed to quantify these depressurisation effects in terms of groundwater level change and groundwater inflow rates during the operations phase and post mine closure. This report provides an assessment of the potential impacts of these changes on groundwater users and the surrounding environment, as well as an assessment of the potential impacts of the Project on groundwater quality.

Syntech Resources has responded to the DES Information Request through an Environmental Values Assessment (EVA). This report supports the EVA to assess the potential environmental impacts associated with the development of the Project in accordance with the DES Information Request.

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2 Regulatory framework

The following sections summarise Queensland and Commonwealth groundwater legislation and policy relevant to the Project.

2.1 Commonwealth Environment Protection and Biodiversity Conservation Act 1999

The EPBC Act is administered by the Department of the Environment and Energy (DoEE). The EPBC Act is designed to protect national environmental assets, known as Matters of National Environmental Significance (MNES). Under the 2013 amendment to the EPBC Act, impacts on groundwater resources were included, and are known as the ‘water trigger’. The Project will be referred to the Commonwealth Minister for the Environment for consideration as to whether it constitutes a ‘controlled action’ under the water trigger provisions and therefore may require approval under the EPBC Act.

The IESC is a statutory body under the EPBC Act that provides scientific advice to the Commonwealth Environment Minister and relevant state ministers. Guidelines have been developed in order to assist the IESC in reviewing CSG or large coal mining development proposals that are likely to have significant impacts on water resources. A summary of the IESC guidelines (CoA, 2018) and where they are addressed within the report is included in Appendix A.

2.2 Queensland regulatory framework

The Queensland Water Act 2000 (Water Act), supported by the subordinate Water Regulation 2002, is the primary legislation regulating groundwater resources in Queensland. The purpose of the Water Act is to advance sustainable management and efficient use of water resources by establishing a system for planning, allocation and use of water.

The water resource planning process provides a framework for the development of catchment specific Water Resource Plans (WRP). A WRP provides a management framework for water resources in a plan area, and includes outcomes, objectives and strategies for maintaining balanced and sustainable water use in that area. A Resource Operations Plan (ROP) implements the outcomes and strategies of a WRP.

Groundwater Management Areas (GMAs) and their component Groundwater Management Units (GMUs) are defined within a WRP. Authorisation is required from the DNRME to take water from a regulated GMA or GMU for specified purposes. The specified purposes are defined under a WRP, the Water Regulation 2002 or a local water management policy.

The Queensland Water Reform and Other Legislation Amendment Act 2014 (WROLA Act) was passed on 26 November 2014. The WROLA Act included a number of key changes to the Water Act; however, commencement of these provisions were deferred under the Water Reform and Other Legislation Amendment (Postponement) Regulation 2015 (Qld).

In November 2016, changes to the WROLA Act were made with the introduction of the Queensland Water Legislation Amendment Act 2015 and the Environmental Protection (Underground Water Management) and Other Legislation Amendment Act 2016 (EPOLA Act), which came into effect on 6 December 2016. The EPOLA Act amends the EP Act and Water Act (Chapter 3), and aims to strengthen the powers of DES in the environmental assessment process, as well as approval commitments to groundwater management.

The amendment application from the proponent was received by the administering authority on 21 November 2016. This predates the requirements for environmental assessments under the EPOLA Act, and as such the additional requirements for groundwater management and assessment are not applicable for this amendment.

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2.2.1 Environmental Protection (Water) Policy 2009

The Environmental Protection (Water) Policy 2009 (EPP Water) provides a framework to protect and / or enhance the suitability of Queensland waters for various beneficial uses. This policy guides the setting of indicators that will protect the environmental values of any resource.

Indicators for environmental values are those quantitative properties of the water, such as physical and chemical parameters, that can be measured. The Australian Water Quality Guidelines (ANZECC, 2000) provide guideline water quality properties for the protection of specific environmental values.

The relevant local groundwater uses and associated values are described in Section 8.

2.2.2 Water Plan (Great Artesian Basin and Other Regional Aquifers) 2017

The Water Plan (Great Artesian Basin and Other Regional Aquifers) 2017 replaced the Water Resources (Great Artesian Basin) Plan 2006 on 2nd September 2017, defines the availability of water within the Great Artesian Basin (GAB) and provides a framework for the allocation and sustainable management of groundwater resources within the plan area. The Project is located in the (Surat) Springbok Walloon groundwater unit (Figure 2.1), the boundaries of which have been defined based on the geological formations that are located in the area of the groundwater unit and stated for the groundwater unit in schedule 3 of the Plan. Using this approach, the Plan seeks to achieve a balance between:  protecting the flow of water to groundwater-dependent ecosystems that support significant cultural and environmental values;  providing for the continued use of authorisations to take or interfere with water;  maintaining and if practicable increasing water pressure in aquifers to preserve the supply of water to bores;  making water available for future development and social and cultural activities that depend on water;  encouraging the efficient use of water by requiring water bores to have watertight delivery systems or be controlled; and  facilitating the operation of efficient water markets and opportunities for the temporary or permanent movement of water.

Additionally, the Plan recognises the state of aquifers and groundwater-dependent ecosystems has changed because of the taking of, and interfering with, water.

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2.2.3 Declared Sub-Artesian areas Queensland includes a number of sub-artesian areas declared under the Water Regulation 2002, which is subordinate legislation to the Water Act. The Project is located in the Greater Western sub-artesian area (previously referred to as the Great Artesian Basin sub-artesian area). Any development works located within a declared sub-artesian area:  require a water entitlement, water permit or seasonal water assignment notice to take or interfere with sub-artesian water, other than for a purpose mentioned in Schedule 11 (column 2) of Water Regulation 2002; and  are assessable developments under the Sustainable Planning Act 2009 for taking sub-artesian water other than solely for a purpose mentioned in Schedule 11 (column 3) of the Water Regulation 2002.

Schedule 11 states that a water entitlement is not required in the Greater Western sub-artesian area for domestic purposes, stock watering or for a prescribed activity intersecting sub-artesian aquifers that are not connected to artesian aquifers. A prescribed activity for general authorisation to take water is listed in Schedule 1 of Water Regulation 2002.

2.2.4 Water Resource (Condamine and Balonne) Plan 2004

The Project area falls within the Water Resource (Condamine and Balonne) Plan 2004. Water to which this plan applies comprises:  water in watercourses and lakes, water in springs disconnected from artesian water, and overland flow water; and  sub-artesian groundwater not connected to artesian water.

The Project is located outside the Condamine and Balonne GMA (Figure 2.1).

2.3 Groundwater licensing for the project

The taking of, or interfering with groundwater, is regulated under the water licensing provisions of the Water Act. The Water Act requires that a water licence is required to take, or interfere with groundwater within areas declared as management areas or declared areas under subordinate Queensland legislation. The Water Resource (Condamine and Balonne) Plan 2004 also states that an entitlement is required for the take of groundwater for purposes other than stock or domestic water supply (e.g. groundwater take for mine dewatering). As discussed in Section 9.4.1, the Project will result in the taking of, or interference with groundwater.

The administering authority for the Water Act is DNRME. The DNRME licensing approach is designed to ensure that the total allocated groundwater take permissible in granted water licences remains within the sustainable yield of the groundwater resource. This approach ensures that individual and cumulative licensed groundwater take does not adversely impact the sustainability of the affected groundwater resource. This regulatory approach also ensures that the licensed take has no significant residual impact on groundwater resources of the Condamine and Balonne water resource.

The proponent will consult with DNRME in relation to its obligations under the Water Act and will comply with any relevant requirements.

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3 Environmental setting

This section describes the regional and local setting of the Project and discusses the location, land use, climate and terrain. The geological setting of the Project area is discussed in Section 5.2.

3.1 Terrain and drainage

Terrain and drainage around the Project area and surrounds are shown in Figure 3.1. The terrain of the area consists of generally low sandstone rises in the northern part with gently undulating and inclined plains over the remainder of the Project area. Overall slopes, generally of less than two percent and drainage lines, trend in a south-southeast direction towards Columboola Creek which is mapped as a watercourse south of the Warrego Highway. The topography to the north of the mining lease boundaries gently slope northwards along drainage line towards the Punch-Bowl Creek watercourse. The terrain is locally timbered with remnant and regrowth vegetation with areas of cleared pasture.

The Project area is located within the Condamine River catchment, which forms part of the Murray-Darling Basin. The Project area is within the headwater catchments of Columboola Creek and Punch-Bowl Creek, which are tributaries of the ephemeral Dogwood Creek. Drainage features in the Project area are ephemeral, with flow only occurring during, and shortly after heavy rainfall events during the wet season.

3.2 Land use

The Project area comprises gently undulating land. Low intensity cattle grazing is the main land use in the Project area. Associated infrastructure on the site includes cattle yards, windmills, dams and water storage tanks. Land use on the Project area also includes the existing coal mining operations of Cameby Downs Mine. Description of the existing mining operations and surrounding resource developments are provided in Section 1.1.1 and 1.1.2.

QGC has developed 25 CSG wells within ML 50233. Within 10 km of the Project area nine petroleum leases have been granted with a further two under application at the time of writing this report. Within 10 km of the Project area, a total of 332 registered CSG or petroleum wells have been drilled. A further 15 wells are currently proposed to be drilled. Figure 3.1 shows the CSG wells surrounding the Project area. The Underground Water Impact Report (UWIR) prepared for the Surat Cumulative Management Area by the Office of Groundwater Impact Assessment (OGIA) in 2016, details impact on groundwater from CSG operations in this area. Response to CSG groundwater extraction that is predicted to decline by more than 5 m within the next three years is referred to as the Immediately Affected Area (IAA). Decline in groundwater levels or pressures by more than 5 m at any time in the future, is referred to as the Long Term Affected Area (LAA). The Project area is located entirely within the Walloon Coal Measures IAA and LAA, and the southern extent is within the Springbok Sandstone LAA (OGIA, 2016). The potential for cumulative groundwater impacts associated with the surrounding land use is discussed in Section 9.4.3.

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3.3 Climate

The climate of the area is sub-tropical, with most rainfall occurring over the summer months. However, the region experiences a relatively low amount of rainfall due to its inland, semi-arid setting. Long-term (since 1887) climate data has been collected by the Bureau of Meteorology (BoM) at the Miles Post Office weather station (Station No. 42023), approximately 17 km west of the Project area. Rainfall and evaporation data is also available from the Scientific Information for Land Owners (SILO) service provided by the Department of Science, Information Technology and Innovation (DSITI). The data is a ‘patched point dataset’, meaning that missing or suspect values are ‘patched’ with interpolated data. Table 3.1 details the average monthly rainfall from BoM Station No. 42023 and the SILO data. Miles is expected to provide a good indication of the long-term climate at the Project given its proximity (i.e. less than 20 km).

Rainfall data from the BoM Station No. 42023 and SILO dataset indicate the area experiences around 642 mm to 649 mm rainfall annually. The SILO dataset indicates similar annual rainfall, and annual evaporation nearly three times annual rainfall (1,815 mm/year).

Table 3.1 Climate data

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual

Rainfall (mm)

Site SILO 90.9 74.7 58.7 34.8 36.8 39.1 35.4 28.2 31 55.8 65.1 90.1 641.5 data*

BoM data (Station No. 96.1 73.3 59.7 36.2 38.6 39.0 36.3 29.4 31.8 53.4 64.5 91.2 649.5 42023)

Evaporation (mm)

Site SILO 230.7 181.3 180.5 130 87.3 66.2 71.5 99.4 145.5 186.3 205.7 230.6 1,814.5 data*

Note: * monthly average based on SILO patched point data from 1889 to 2016.

Recent rainfall years have been put into historical context using the Cumulative Rainfall Departure (CRD) method. This method is a summation of the monthly departure of rainfall from the long-term average monthly rainfall. A rising trend in the CRD plot indicates periods of above average rainfall, whilst a falling slope indicates periods when rainfall is below average.

Figure 3.2 presents the CRD graph for the Project area using BoM monthly rainfall data. The CRD graph indicates that the area has experienced distinct cycles of above average and below average rainfall. The CRD graph indicates that since 1990 the Project area experienced generally below average rainfall between 1990 and 1995, 1998 to 2009, and from 2015. Conversely the area experienced above average rainfall between 1995 and 1998, and in 2010. Between 2012 and 2014 rainfall was consistent with the long-term average.

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Figure 3.2 Cumulative rainfall departure

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4 Groundwater monitoring network

Syntech Resources has established a groundwater monitoring network that were sited to provide a broad level of coverage across the mine area and serve as long-term monitoring facilities for the mine. The bores were located outside of the mining area to initially provide baseline data, and subsequently for assessment of impacts from mining on the coal seam hydrogeology. The groundwater monitoring network comprises six monitoring bores across the Project area, as shown in Figure 4.1. Table 4.1 presents the bore details for each monitoring bore. The bores were originally drilled for exploration purposes between October 2002 and April 2004, and were subsequently converted as groundwater monitoring bores in May 2004 targeting the MA1 and MA2 seams, which form a single hydrogeological unit in the Project area. Groundwater monitoring has been undertaken from these monitoring bores since there establishment. In 2016, CD018 was decommissioned and grouted.

Each monitoring bore consists of Class 12, 50 mm, uPVC with a hand-slotted screen. The gravel pack comprises graded 2 mm to 3 mm washed rounded gravel. The bore annulus was sealed with a 1.5 m bentonite plug above the gravel pack. The annulus above the bentonite seal was backfilled with drill cuttings and sealed with cement at the surface.

An additional five monitoring bores have been established from selected exploration bores across the Project area, with the data used as part of ongoing studies for the Surat Cumulative Management Area being undertaken by the OGIA. These bores have been left as open holes with only the surface casing in place and as installed when drilled. Table 4.2 presents the bore details for each of these bores used for this additional monitoring.

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Table 4.1 Monitoring bore summary

Combined Collar Bore Casing Slotted MA1 MA2 seam Gravel pack Predicted life Bore ID Easting Northing elevation depth stick up interval (mbGL) (mbGL) thickness (mbGL) expectancy (mAHD) (maGL) (mbGL) (mbGL) (m)

Decommissioned in CD018 237983 7049824 322.1 63 44.1 - 44.9 45.3 - 46.2 1.7 0.5 41.5 - 47.5 40 - 63 2016

CD034C 235706 7054194 350.6 47.4 36.6 - 39.3 39.3 - 40.6 4 0.3 34.9 - 46.9 34.8 - 47.4 2071 - 2075

CD036R 235094 7052931 338.6 60 47.5 - 49.2 not present 1.7 0.36 39.4 - 47.4 38.3 - 60 2076 – 2080

CD037C 235563 7053320 346.1 50.3 44 - 45.5 45.7 - 48.7 4.6 0.4 39.5 - 47.5 39 - 50.3 2076 - 2080

CD056 236505 7051782 328.2 58.1 53.7 - 57.2 57.2 - 57.7 4.1 0.4 53.2 - 59.2 46.1 - 58.1 2026 - 2030

CD065 235953 7053638 343.6 48 29 - 32.5 not present 3.5 0.6 27 - 33 27 - 48 2071 - 2075

Notes: Coordinates in MGA94, Zone 56 mAHD - metres above Australian height datum mbGL - metres below ground level maGL - metres above ground level Predicted life expectancy based on proposed mine plan for the Project

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Table 4.2 Additional OGIA monitoring bore summary

Combined Collar Casing Casing Bore depth Coal seam monitored seam Open hole Predicted life Bore ID Easting Northing elevation stick up depth (mbGL) thickness (mbGL) expectancy (mAHD) (mbGL) (maGL) (mbGL) (m)

KG1, KG2 between CD470 235439 7051153 331.8 70.3 1.0 0.6 25 25 – 70.3 2036 - 2040 53.2 m & 55.3 m

No seam present in open CD476P 237793 7049661 322.4 51.6 0.0 0.4 41.1 41.1 – 51.6 2081 – 2085 section of borehole

MS between 35.2 m & CD466C 237241 7049755 323.9 42.8 1.6 0.4 35.2 35.2 - 42.8 2081 – 2085 36.8 m

MA1U, MA1, MA2, MA3, CD472P 236998 7050076 325.4 65.6 MA4, NG1 between 49 m 4.6 0.9 41.5 41.5 – 65.6 2031 - 2035 & 59.7 m

KGU1, KGU2, KG1, KG2 CD382C 235731 7051137 330.2 73 3.2 0.4 36 36 - 73 2031 - 2035 between 44.4 m & 53.6 m

Notes: Coordinates in MGA94, Zone 56 mAHD - metres above Australian height datum mbGL - metres below ground level maGL - metres above ground level Predicted life expectancy based on proposed mine plan for the Project

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5 Geological setting

5.1 Regional geology

The Project is located on the eastern flank of the northern Surat Basin, which stratigraphically overlies the Bowen Basin. The Surat Basin comprises Jurassic to Cretaceous aged sandstones, siltstones, and mudstones deposited in a predominantly fluvio-lacustrine depositional environment. The stratigraphy of the Surat Basin relevant to the Project is shown in Table 5.1. Figure 5.1 shows the surface geology at the Project area and surrounds.

The oldest sediments throughout the Surat Basin are the early to middle Jurassic aged Precipice Sandstone, Evergreen Formation, and Hutton Sandstone. These units subcrop approximately 25 km northeast of the Project area and dip to the southwest. Within the Project area, these units are between 600 m to 1,100 m below ground level (mbGL). The Hutton Sandstone is unconformably overlain by the Eurombah Formation, which in turn is overlain by the Walloon Coal Measures. The Eurombah Formation is approximately 95 m thick in the Project area and comprises lithic conglomeratic sandstone with mudstone and siltstone beds.

The Project will not intersect the Precipice Sandstone, Evergreen Formation, Hutton Sandstone or the Eurombah Formation, nor do these geological units subcrop within 10 km of the Project boundary. As such, none of these geological units have been considered further in this assessment.

The Cameby Downs Mine intersects coal seams associated with the Walloon Coal Measures of the Injune Creek Group. The Walloon Coal Measures subcrop in a broad, northwest trending arc, up to 70 km wide along the northeast and northern margins of the Surat Basin. The Walloon Coal Measures are further split into three distinct units, the Juandah Coal Measures, Tangalooma Sandstone, and the Taroom Coal Measures. The existing Cameby Downs Mine and the Project target the economic coal seams (i.e. Kogan, Macalister and Wambo seams) of the Juandah Coal Measures.

The Walloon Coal Measures are unconformably overlain by the late Jurassic Kumbarilla Beds, which are stratigraphic equivalent of the Springbok Sandstone, Westbourne Formation and the Gubberamunda Sandstone. Only the Springbok Sandstone is present in the Project area, and outcrops in the northern part of the Project area (Figure 5.1). The Springbok Sandstone comprises labile sandstones, siltstone, mudstone and some conglomerate. The Springbok Sandstone thickens to the southwest with the general dip of stratigraphy. The Westbourne Formation and the Gubberamunda Sandstone occur as outcrop 7 km southwest (down-dip) of the Project, but do not occur in the Project area.

The surface geology map (Figure 5.1) also shows the presence of Tertiary and Quaternary age sediments, which occur as thin surficial units comprising clays, silts, sands and gravels. Thicker Quaternary alluvial deposits associated with Condamine River flood plain occur some 17 km to south of the Project area.

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Table 5.1 Surat Basin stratigraphy – northeastern area

Approximate Age Stratigraphic unit Description thickness

Quaternary Alluvium (Qa, Qpf) Clay, silt, sand, and gravel Surficial

Rolling Marine grey mudstone and siltstone Early Not present in the Downs Wallumbilla Formation (Ku) with minor fine grained glauconitic Cretaceous Project area Group and calcareous sandstone interbeds

Fine to coarse and pebbly, poorly sorted, friable, cross-bedded, Gubberamunda Not present in the quartzose to sub-labile sandstone. Sandstone (Jig) Project area Minor interbedded siltstone and mudstone.

Although not identified in the Late Kumbarilla Fluvial-lacustrine sediments: fine- Project area, Westbourne Jurassic Beds (JKk) grained sandstone interbedded with probably present Formation siltstone, claystone, minor coal. along the southwestern boundary

Clayey lithic sublabile to very lithic Springbok sandstone; calcareous in part; less than 30 m Sandstone interbedded with carbonaceous mudstone and siltstone. Injune Creek Lithic, labile sandstone, interbedded Group (Ji) with siltstone, mudstone and coal, with coal deposition more frequent Juandah Coal towards top. Argillaceous up to 220 m Measures component of sandstone is mainly authigenic. Walloon Includes the target coal seams Coal Lithic, labile sandstone, medium Measures Tangalooma grained with an argillaceous matrix. (Jw) approx. 50 m Sandstone Numerous intra-formational conglomerate beds.

Middle Sub-labile, medium grained Jurassic Taroom Coal sandstone grading upwards to up to 145 m Measures interbedded sandstone, siltstone, mudstone and coal.

Lithic conglomeratic sandstone with Eurombah Formation approx. 95 m mudstone and siltstone beds.

Poorly sorted, coarse to medium- grained, feldspathic sub-labile sandstone (at base) and fine-grained, Hutton Sandstone (Jlh) well-sorted quartzose sandstone (at approx. 255 m top); minor carbonaceous siltstone, Bundamba mudstone, coal and rare pebble Group conglomerate.

Labile and sub-labile, sandstone overlain by carbonaceous mudstone, Evergreen Formation (Je) approx. 161 m siltstone and minor coal; local oolitic Early ironstone. Jurassic Thick-bedded, cross-bedded, pebbly quartzose sandstone, minor lithic Precipice Sandstone (Jp) approx. 81 m sub-labile sandstone, siltstone, mudstone.

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5.2 Geology of the Project area

The following main stratigraphic units occur within the Project area and surrounds (from oldest to youngest):  Walloon Coal Measures;  Springbok Sandstone;  Tertiary sediments; and  Quaternary sediments.

Each of the main stratigraphic units is discussed in further detail below.

5.2.1 Walloon Coal Measures

The Walloon Coal Measures, part of the Injune Creek Group, unconformably overly the Eurombah Sandstone. The Walloon Coal Measures subcrop in a broad, northwest trending arc, up to 70 km wide along the northeast and northern margins of the Surat Basin. The sub-group is separated in to three stratigraphic units. The lowermost unit in the Project area is the Taroom Coal Measures. The unit is up to 145 m thick in the Project area and comprises sub-labile, medium grained sandstone grading upwards to interbedded sandstone, siltstone, mudstone and coal. The Tangalooma Sandstone is approximately 50 m thick and conformably overlies the Taroom Coal Measures. The unit comprises lithic, labile, medium grained sandstone with an argillaceous matrix and numerous intra-formational conglomerate beds.

The uppermost unit of the Walloon Coal Measures in the Project area is the Juandah Coal Measures which comprises lithic, labile sandstone interbedded with siltstone, mudstone and coal. Coal deposition is more frequent towards top of the unit. The Juandah Coal Measures are up to 220 m thick in the Project area.

The Walloon Coal Measures subcrop in the north east of the Project area and dip between one and three degrees to the southwest. The subcrop forms the northeast boundary of the proposed open cut mine. The main economic coal seams in the region are within the Walloon Coal Measures and include the target coal seams for the Project as well as for CSG production within the region (OGIA, 2016).

The Juandah Coal Measures occur at depths of between 30 mbGL to 125 mbGL in the Project area and are the coal seams being mined at the Project. Exploration drilling has identified three coal horizons and 12 individual coal seams, including:  Kogan (KG1, KG2, KG3, and KG4);  Macalister (MA1, MA2T, MA2B, MA3, and MA4); and  Wambo (WM1, WM2, and WM3).

The MA1 and MA2T/B coal seams comprise the main economic resource. Figure 5.2 shows the coal seams of the Juandah Coal Measures. Figure 5.3 shows the WM3 seam floor structure and overburden thickness above the KG1 seam. These layers represent the upper and lower bound of the Juandah Coal Measures.

Figure 5.2 indicates the typical depth of weathering at Cameby Downs Mine to be around 26 m below ground level.

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5.2.2 Springbok Sandstone

Within the Project area, the Springbok Sandstone conformably overlies the Walloon Coal Measures. The unit comprises clayey, lithic, sub-labile to very lithic sandstone, calcareous in part; interbedded with carbonaceous mudstone and siltstone. The Springbok Sandstone gently dips and thickens to the southwest. Pre-Tertiary weathering has chemically altered the sediments resulting in silicified, kaolinised and ferruginised sandstone.

5.2.3 Tertiary sediments

Tertiary sediments are present in the northeast part of the Project area (Figure 5.1) and unconformably overlie the older Jurassic and Cretaceous age sediments of the Surat Basin. The Tertiary cover is generally thin in the Project area and comprises deeply weathered clayey sub-labile to quartzose sandstone, sandy claystone, laminated siltstone, and minor conglomerate.

5.2.4 Quaternary sediments Quaternary sediments associated with the Condamine River and its tributaries unconformably overlie the Springbok Sandstone and Tertiary Sediments (where present). The Condamine river alluvium is a broad term used to describe the alluvial and sheetwash deposits of the Condamine River and its tributaries. The Quaternary sediment in the Project area consists primarily of thin sheetwash deposits of silty clay to sandy clay.

5.3 Structural geology

The Surat Basin is characterised by several anticlinal and synclinal structures that are largely controlled by reactivation of Triassic basement fault systems (QGC, 2012). One of these structures is the north-south trending Burunga-Leichhardt thrust fault, located approximately 12 km west of the Project area (Figure 5.1).

Although exploration drilling has identified the presence of laterally discontinuous faults, no other significant or extensive faults have been identified in the Project area or its surrounds.

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6 Hydrogeology

This section details the existing hydrogeology of the Project area and surrounds, by describing the hydrogeological properties of each geological unit. The GAB is a groundwater basin comprising various parts of other geologic basins, which include the Surat Basin. Aquifers within the Surat Basin include the Precipice Sandstone, Hutton Sandstone, Kumbarilla Beds, and the Gubberamunda Sandstone.

Table 6.1 summarises the stratigraphic units occurring within the Project area and immediate surrounds. The primary groundwater bearing units are the unconsolidated alluvial sediments (where saturated), the Springbok Sandstone, the coal seams within the Walloon Coal Measures, and the Hutton Sandstone and Precipice Sandstone.

Table 6.1 Groundwater characteristics of geological units within the Project area

Geological age Geological unit Status

Quaternary / Tertiary alluvial sediments ephemeral groundwater present

Late Jurassic Springbok Sandstone unsaturated in the Project area

Walloon Coal Measures (coal seams) confined aquifer

Middle Jurassic Walloon Coal Measures (interburden and aquitard underburden)

Middle / early Jurassic Hutton Sandstone and Precipice Sandstone confined aquifer

6.1 Quaternary sediments

Quaternary sediments are associated with the Condamine River and its associated tributaries. The Quaternary sediments comprise silty clay to sandy clay. Although 1:250,000 geology mapping of the area suggests the Quaternary sediments cover much of the Project area, exploration drilling data indicates that, where present, the Quaternary sediments are thin and unsaturated. Localised disconnected zones of saturated alluvium may be present along Columboola Creek, approximately 1 km southwest of the Project area (Figure 3.1). Groundwater recharge to the Quaternary sediments occurs via direct rainfall. Where saturated, alluvium loses water via downward leakage to the underlying system such as the Tertiary sediments and/or the Springbok Sandstone. The Condamine River is approximately 17 km south of the Project area (Figure 3.1), the Quaternary sediments near the river form a productive aquifer. The Quaternary sediments in the Project area are unsaturated and are far enough away from the Condamine River that they are disconnected from the Condamine River alluvium. Where groundwater is present in the alluvium, the flow direction is from north to south and follows topography.

No groundwater supply bores target the Quaternary sediments in the Project area or surrounds (refer to Section 6.9.3), this is due to the general lack of saturation or reliable water supply in these sediments.

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6.2 Tertiary sediments

Tertiary sediments are present in the northeast part of the Project area (Figure 5.1) and unconformably overlie the older Jurassic and Cretaceous age sediments of the Surat Basin. The Tertiary cover is generally thin in the Project area and comprises deeply weathered clayey sub-labile to quartzose sandstone, sandy claystone, laminated siltstone, and minor conglomerate.

Groundwater recharge to the Tertiary sediments occurs via direct rainfall and diffuse rainfall seepage through the thin overlying Quaternary sediments. Groundwater discharge is via seepage to the underlying groundwater system.

No groundwater supply bores target the Tertiary sediments in the Project area or surrounds (refer Section 6.9.3), which is due to the general lack of saturation or reliable water supply in these sediments.

6.3 Springbok Sandstone

The Springbok Sandstone is the lowermost unit of the Kumbarilla Beds. It outcrops in the northeastern corner of the Project area and subcrops below the Quaternary sediments elsewhere. The Springbok Sandstone gently dips and thickens to the southwest and comprises clayey lithic sub-labile to very lithic sandstone, calcareous in part, interbedded with carbonaceous mudstone and siltstone. Pre-Tertiary weathering has chemically altered the sediments resulting in silicified, kaolinised and ferruginised sandstone.

The outcrop and subcrop of the Kumbarilla Beds, which includes the Springbok Sandstone, form a groundwater recharge zone for the GAB (Smerdon et al., 2012). Figure 6.1 shows the Project area is within the mapped extent of the GAB groundwater recharge beds. Although regionally the Springbok Sandstone forms a productive aquifer of the Surat Basin, exploration drilling indicates the unit is generally unsaturated within the Project area. The Springbok Sandstone will become saturated as the unit dips below the regional water table to the southwest of the Project area.

Recharge of the Springbok Sandstone occurs via direct rainfall and diffuse rainfall seepage through the thin overlying Quaternary sediments. Regional groundwater flow in the Springbok Sandstone is down dip, towards the southwest. Discharge is via downward leakage to underlying sediments and down gradient of the Project area.

No groundwater users within 10 km of the Project area target the Springbok Sandstone (refer to Section 6.9.3).

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6.4 Walloon Coal Measures

As discussed in Section 5.1, the Walloon Coal Measures are separated into three stratigraphic units. The uppermost unit in the Project area is the Juandah Coal Measures which contain the main economic coal seams for the Project. The Juandah Coal Measures comprise lithic, labile sandstone interbedded with siltstone, mudstone and coal. Coal deposition is more frequent towards top of the unit. The Taroom Coal Measures and the Tangalooma Sandstone underlie the Juandah Coal Measures and form a thick confining aquitard between the Juandah Coal Measures and the underlying Hutton Sandstone and Precipice Sandstone. Regionally, the Springbok Sandstone is separated from the coal seams of the Walloon Coal Measures by an aquitard approximately 15 m thick (Office of Groundwater Impact and Assessment [OGIA], 2016).

The main water bearing units of the Walloon Coal Measures are the coal seams which comprise approximately 10% of the total thickness of the unit (OGIA, 2016). Hydraulic conductivity within the Walloon Coal Measures is generally associated with secondary porosity through fractures, and cleats within the coal seams.

6.5 Hydraulic parameters

AGE (2006) completed in-situ permeability tests on six monitoring bores within the Project area. Table 6.2 presents the measured hydraulic conductivity of the MA1 / MA2 coal seams. The median hydraulic conductivity for the MA1 / MA2 coal seams is 0.16 m/day which is representative of shallow coal seams in the region. The coal seams will have a higher hydraulic conductivity compared to the interburden due to flow via fracturing and cleats within the coal. The hydraulic conductivity data presented in Table 6.2 is comparable to that published by OGIA (2016).

Table 6.2 Hydraulic testing results of the MA1 / MA2 coal seams

Bore ID Hydraulic conductivity (m/day)

CD018 1.3

CD034C 0.1

CD036R 0.02

CD037C 0.16

CD056 0.2

CD065 dry bore

Median 0.16

Hydraulic testing at other mines in the area indicate the hydraulic conductivity of the interburden is approximately 0.009 m/day, several orders of magnitude lower compared to the coal seams (AGE 2013).

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6.6 Existing data and monitoring

Groundwater level data has been collected from the groundwater monitoring bores within the Project area from 2004 to present. Figure 6.2 presents the groundwater level hydrograph for the groundwater monitoring bores, which screen the MA1 / MA2 coal seams. Groundwater levels are between 290 mAHD and 318 mAHD. As detailed in AGE (2015), the elevated water level readings for CD034C in the order of 330 mAHD is considered an anomaly and not representative of the formation groundwater level following bore construction. Natural groundwater level fluctuations would show a similar trend to the CRD. However, all bores show a slight decline relative to the CRD and therefore are impacted by either passive drainage to the existing open cut or CSG extraction near the Project area.

Figure 6.2 Groundwater level hydrographs

Figure 6.3 presents the potentiometric surface for the MA1 / MA2 coal seams. The regional groundwater flow direction in the coal seams is from north to south-southwest. The removal of associated water during CSG extraction is expected to have impacted the groundwater level and flow direction in the Walloon Coal Measures. Groundwater flow within the Project area is towards the southwest, which is down dip within the Walloon Coal Measures and most likely a function of CSG extraction. Additional groundwater level data has been provided by Syntech Resources from selected exploration bores across the Project area. This data was collected in June 2017 as part of ongoing studies for the Surat Cumulative Management Area by the OGIA and is presented in Table 6.3. The data shows groundwater levels in these bores ranging between 292 m AHD and 308.2 mAHD. These boreholes are open holes with surface casing installed typically to the base of weathering. Therefore, the open section most probably intersects groundwater from other coal seam strata above and below the target Macalister (MA1 / MA2) coal seams. As such, the more elevated groundwater levels between 304 mAHD (CD14C) and 308.2 mAHD (CD419C) are considered a composite of all coal seam groundwater levels and do not reflect groundwater elevation specific to the Macalister (MA1 / MA2) coal seams.

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Table 6.3 Additional site groundwater level data (June 2017)

Bore Water TOC Bore SWL Easting Northing Elevation depth level height name (mAHD) (mTOC) (mTOC) (magl)

CD14C 237298.05 7050322.20 323.87 28.0 19.00 0.00 304.9

CD332C 238532.61 7050699.33 325.46 40.3 26.60 0.22 299.1

CD332CR 238532.61 7050699.33 325.46 45.9 25.72 0.46 300.2

CD339 237169.00 7050819.00 324 35.2 27.83 0.46 296.6

CD369C 238197.00 7050456.00 325 32.1 24.50 0.20 300.7

CD370 238469.09 7050391.13 324.27 26.4 22.60 0.19 301.9

CD379C 238445.08 7050141.64 323.35 33.5 23.79 0.48 300.0

CD382C 235731.30 7051137.00 329.78 73.0 34.40 0.40 295.8

CD419C 237463.30 7049428.00 321.38 80.0 13.46 0.29 308.2

CD463 235093.74 7050672.78 331.46 ND 36.45 0.00 295.0

CD463C 235093.74 7050672.78 331.46 83.7 39.74 ~0.25 292.0

CD466C 237241.50 7049755.00 323.47 42.8 23.77 0.41 300.1

CD466P 237239.00 7049756.00 323.47 >26 23.50 0.43 300.4

CD470 235439.00 7051153.00 331.17 70.3 32.87 0.60 298.9

CD472C 236998.93 7050076.12 324.49 63.4 22.97 0.26 301.8

CD472P 236998.9 7050076.1 324.49 65.6 27.75 0.93 297.7

CD475 237497.64 7049686.26 323.01 48.4 24.47 ~0.5 299.1

CD476A 237790.00 7049655.00 321.96 ND 22.67 0.00 299.3

CD476C 237793.61 7049660.98 321.96 63.4 22.69 0.77 300.0

CD476P 237793.60 7049661.00 321.96 51.6 22.87 0.42 299.5

CD783 236744.82 7052378.48 332.04 46.7 19.00 0.51 295.1

Notes: mTOC – metres below top of casing TOC – top of casing SWL – standing water level ND - water level not measured/recorded

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6.7 Groundwater quality

Groundwater quality data provides useful information on the geology and groundwater regime. This data can also be assessed against the known uses and values of groundwater.

A review of 103 groundwater samples was completed for the Project. This data includes data provided by Syntech Resources from selected exploration bores across the Project area as part of ongoing studies for the Surat Cumulative Management Area by the OGIA. The samples were collected between April 2009 and June 2017 from the five monitoring bores within the Project area and the five exploration bores selected as part of ongoing studies for the Surat Cumulative Management Area being undertaken by the OGIA.

Appendix B presents a full summary of the groundwater quality data, and time series plots for pH, electrical conductivity (EC), total dissolved solids (TDS), sulfate and total metals.

Salinity is a key constraint to water management and groundwater use, and can be described by TDS concentrations, which are commonly classified on a scale ranging from fresh to extremely saline. FAO (2013) provide a useful set of categories for assessing salinity based on TDS concentrations as follows: fresh water <500 mg/L brackish (slightly saline) 500 to 1,500 mg/L moderately saline 1,500 to 7,000 mg/L saline 7,000 to 15,000 mg/L highly saline 15,000 to 35,000 mg/L brine >35,000 mg/L

Table 6.4 presents a summary of the water quality data. Groundwater in the MA1 / MA2 coal seams is brackish to highly saline with elevated levels of sodium and chloride, making it generally unsuitable for livestock watering (see Section 8.3). This also precludes groundwater use for sustaining a potable source and other agricultural uses such as irrigation.

Table 6.4 Groundwater quality for the MA1 / MA2 coal seams

Parameter Units Min. Max. Median. Geomean

pH (field) 5.5 8.4 6.8 6.7

Electrical conductivity (EC) S/cm 720 35,300 13,790 13,242

Total Dissolved Solids (TDS) mg/L 468 25,200 10,050 9,762

Bicarbonate (HCO3) mg/L 55 586 325 236

Sulphate (SO4) mg/L 1 1,040 18 27

Chloride (Cl) mg/L 591 14,500 4,920 4,549

Calcium (Ca) mg/L 46 968 536 326

Magnesium (Mg) mg/L 27 829 388 283

Sodium (Na) mg/L 341 7,610 1,700 2,015

Potassium (K) mg/L 4 71 26 23

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The proportions of the major anions and cations were analysed to determine the hydrochemical facies of the MA1 / MA2 coal seams. The anion-cation balance is shown on the Piper diagram in Figure 6.4. The data shows that groundwater within the MA1 / MA2 coal seams of the Walloon Coal Measures is predominantly sodium-chloride (Na-Cl) type. There is a trend from no dominant cation in the up gradient bores, towards sodium dominant in down gradient bores (Figure 6.3). This trend reflects a natural progression of carbonate dissolution in the unsaturated zone during recharge, followed by precipitation of carbonates as groundwater moves through the coal seam.

Figure 6.4 Piper diagram The reason for the elevated sulfate levels in CD034C is not apparent, but maybe a result of oxidation within the intersected coal seam which would reflect the slightly lower and more acidic pH measured in this monitoring bore. In spite of the elevated sulfate levels at this location, the groundwater remains dominated by sodium and chloride.

The time series plots of groundwater quality presented in Appendix B show that whilst there is some variability in the cation and anion levels (i.e. EC, TDS and sulfate levels) in the groundwater across the Project area, the groundwater is dominated by sodium and chloride. Concentrations of dissolved metals were either below the laboratory limit of reporting, or below the respective livestock watering (cattle) or drinking waters guidelines.

6.7.1 Geochemistry SRK Consulting (2012) describes the potential for acid and metalliferous drainage (AMD) associated with the overburden, coal wash rejects and raw coal stockpiles and the dispersive character of overburden and washery wastes. Key findings from the report include:  the overburden consists primarily of non-acid forming material, however, there is potential for existing salinity to be washed from the overburden in response to rainfall events;  the carbonaceous units in the overburden may have a capacity to generate acid;  coal rejects should be managed to control formation and release of acid drainage; and  precautions should be taken to prevent water flow over the dispersive materials of overburden dumps so as to control gully erosion. Based on the above comments, it is assessed that whilst there is some minor potential for acid generation this will be managed throughout the life of mine. This will be achieved by containment of any waste rock material identified as having a high acid forming risk potential, within in-pit waste rock emplacement areas (Yancoal, 2016).

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6.8 Groundwater recharge, distribution and flow

Groundwater recharge to the Walloon Coal Measures is very low due to the relatively low annual rainfall and high evaporation rates (refer to Section 3.3), and the low permeability of overlying strata (refer to Section 6.4). Recharge occurs via direct rainfall where the unit outcrops and via seepage from overlying strata, and is assessed to be low (0.0 mm/year to 0.2 mm/year) as reported in the OGIA 2012 UWIR report (GHD, 2012).

Airlift data from drilling in the Project area indicates the groundwater yields are between 0.6 L/s and 2.4 L/s, with a median yield of 1.2 L/s. The bore census conducted in 2017 (refer Section 6.9.3) identified there is no significant use of groundwater by landholders surrounding the Project area with the nearest water supply bore located approximately 6.5 km south of the ML boundary. Other users surrounding the Project area include CSG operations, and the existing mining operations in the Project area.

The main productive aquifers present within the Project area include the Precipice Sandstone, Hutton Sandstone, and Springbok Sandstone. Regionally, these aquifers are used extensively for stock and domestic and stock intensive water supply due to being laterally continuous, permeable, and containing significant storage (OGIA, 2016). However, in some areas, their hydraulic properties may be closer to the character of aquitards than aquifers (OGIA, 2016). The permeable units are separated by thick sequences of low permeability aquitards, confining the aquifers. Within the Project area, the main aquitards are the Evergreen Formation, the lower sequence of the Walloon Coal Measures, and the overburden separating the Springbok Sandstone and the coal seams of the Walloon Coal Measures (refer to Section 6.4).

Recharge to the GAB occurs via direct infiltration from rainfall along the outcrops and via seepage from streams or overlying strata. Groundwater in the GAB generally flows towards the south, southwest, and west at velocities of one to five millimetres per year (OGIA, 2016). Discharge occurs via springs, rivers, vertical leakage, subsurface flow into adjoining areas, and groundwater extraction across the basin.

Although groundwater quality in the GAB varies across aquifers, it is generally fresh to brackish and suitable for stock watering purposes, with salinity averaging 1,900 mg/L (OGIA, 2016).

As discussed in Section 6.2, the Project is partially located in the mapped extent of the GAB groundwater recharge area of the Kumbarilla Beds. This unit outcrops in the north-western part of the Project area and subcrops below the Quaternary sediments. The Springbok Sandstone is generally unsaturated and does not form a significant aquifer in the Project area. The Hutton Sandstone is more than 500 mbGL in the Project area and is separated from the target coal seams by a thick sequence of sandstone, siltstone, mudstone, and coal.

Two registered groundwater bores target the Hutton Sandstone within 10 km of the Project area.

6.9 Groundwater use

6.9.1 Approved Cameby Downs Mine

As discussed in Section 1.1.1, the Cameby Downs Mine is currently approved to extract up to 2.8 Mtpa of ROM coal over a mine life of approximately 45 years. AGE (2013) completed a GIA which including developing a groundwater model to predict the impacts from the existing Cameby Downs Mine. The previous model conservatively predicted the zone of depressurisation would extend approximately 8.5 km southwest of the Project area (AGE, 2013).

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6.9.2 Coal seam gas Extensive CSG development has resulted in significant depressurisation of the coal seams within the Walloon Coal Measures. Groundwater pressures drop rapidly in the higher permeability coal seams but fall more slowly in the lower permeability interburden (siltstones and sandstone) and disconnected coal seams (OGIA, 2016). Generally, the pressure impacts from CSG extraction are limited to the immediate vicinity of the active CSG extraction areas by QGC (OGIA, 2016).

Groundwater modelling by OGIA (2016) predicts that regionally, CSG extraction from the Walloon Coal Measures will result in some depressurisation in the Springbok Sandstone. However, at present this is minimal.

The OGIA (2016) groundwater model predicts there will be no impact to the Hutton Sandstone from CSG extraction.

6.9.3 Registered groundwater users DNRME maintains the GWDB with the details of registered bores (DNRME, 2017). An initial review of the database was used to identify the locations of registered bores that could potentially be impacted by the Project. Figure 6.5 shows the location of registered landholder bores within 10 km of the Project area and a summary of relevant data regarding each bore is presented in Table C.1 in Appendix C.

A bore census was subsequently undertaken by ENRS Pty Ltd (ENRS) for the Project in October 2017 to address uncertainties identified from the review of the GWDB such as registered bores with little or no details relating to geology, groundwater, bore construction or the bore’s current status. A copy of the bore census report is provided in Appendix D. The report confirms the registered bores identified were either monitoring bores associated with petroleum exploration or CSG activities, had been decommissioned or did not exist. The bore census assessed 30 privately-owned properties surrounding the Cameby Downs Mine, across an area of more than 150 square kilometres, resulted in identification of only one non-mining, or CSG related groundwater bore being a stock bore in use and two monitoring bores, which include:  RN123511 (stock bore); and  RN168040 and RN168041, which are two of Cameby Mine’s monitoring bores (CD036R and CD018 respectively).

Details available for the stock bore (RN123511) identifies the bore is screened into the Hutton Sandstone, 520 mbGL to 797 mbGL, which is well below the target coal seams of the Project.

One unregistered bore (windmill) was identified on the Oxford Downs property (Gospers Road) for which bore records are not available. This bore was assessed to not be in use and the property manager confirmed there were no active bores on the property as water is sourced from the creek.

In conclusion, the 2017 bore census has identified that there is no significant use of groundwater by landholders surrounding the Project area with the nearest water supply bore (RN123511) located approximately 6.5 km south of the ML boundary and outside the predicted zone of impact from the Project (refer Section 9.4.5).

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6.10 Groundwater dependent ecosystems

A groundwater dependent ecosystem (GDE) is one in which the plant and/or animal community is dependent on the availability of groundwater to maintain its structure and function. Desktop mapping of potential GDEs through-out Queensland (DSITI, 2017a and BoM, 2017[1]) indicates:  Drainage features in the north of the Project area (mainly Drainage Lines 5 and 6, and associated minor drainage features [refer Figure 3.1]) potentially receive surface expression of groundwater (possibly supporting an aquatic ecosystem) and are potentially associated with subsurface presence of groundwater (possibly supporting terrestrial riparian vegetation - mapped as ‘treed vegetation fringing channels on unweathered sandstones’).  A patch of terrestrial vegetation in ML 50233 (Figure 6.6) and ground truthed by Ecosure [2017] as RE 11.5.1) is potentially associated with subsurface presence of groundwater (mapped as ‘treed non-wetland vegetation on alluvia’).  Patches of terrestrial vegetation south of ML 50233 (Figure 6.6) are potentially associated with subsurface presence of groundwater (mapped as ‘treed non-wetland vegetation on alluvia’).

The desktop GDE mapping (DSITI, 2017 and BoM, 2017) of the Project locality is not based on site specific work and has a moderate confidence level in regard to the potential for GDEs along the drainage features and a low confidence level in regard to the patch of terrestrial vegetation in ML 50233.

[1] Note: Bureau of Meteorology (2017) mapping is based on the DSITI (2017) mapping as of June 2017.

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Based on this review of the GDE mapping (DSITI, 2017 and BoM, 2017) and the site surveys by Ecosure (2017) and DPM Envirosciences (2017), the following conclusions can be made in relation to the presence/absence of GDEs for the Project locality:  Drainage Lines 5 and 6 (and associated minor drainage features [Figure 3.1]) are not likely to support aquatic or terrestrial GDEs because: o any alluvial aquifers that may be associated with these drainage features would be thin, perched, discontinuous and temporal, and also hydraulically separated from the regional groundwater system, and no permanent alluvial aquifers have been identified; o the vegetation that occurs along these drainage lines (RE11.7.4 and RE11.7.7) also occurs more widely across the landscape and is not restricted to areas where the vegetation could potentially access groundwater (Ecosure, 2017); and o the aquatic flora and fauna present along these drainage lines are generally well adapted to wetting and drying cycles expected in these ephemeral systems (DPM Envirosciences, 2017).  The patch of terrestrial vegetation in ML 50233 (mapped as RE 11.5.1) is not likely to be dependent on groundwater because the occurrence of this regional ecosystem is dominated by Ironbark Woodlands and comprises tree species that occur more widely across the landscape and are not restricted to areas where the vegetation could potentially access groundwater (Ecosure, 2017).  There are no other drainage lines, watercourses, wetlands or springs surrounding the Project in the maximum drawdown zone (including those patches of terrestrial vegetation south of ML 50233) likely to support GDEs that are connected to the regional groundwater system and subject to any predicted drawdown impacts by the Project.

The presence of stygofauna in groundwater within the Project area was assessed by Ecowise Environmental (2010). A total of seven monitoring bores were sampled and no evidence of stygofauna was found. The high electrical conductivity (EC) of groundwater in the area suggests there is unlikely to be stygofauna communities in the Project area.

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7 Conceptual groundwater model

This section describes the processes that control and influence the storage and movement of groundwater in the hydrogeological system. Figure 7.1 represents a north to south cross-section through the Project area. Figure 5.1 shows the location of the cross-section. The cross-section shows graphically the main processes and mechanisms influencing the groundwater regime including recharge, flow directions and discharge.

The geology comprises a thin cover of Tertiary and Quaternary sediments overlying Jurassic strata which dip to the southwest. The main groundwater bearing units in the Project area are the Jurassic coal seams. The Condamine River alluvium does not form a permanent, saturated aquifer in the Project area. Although the Springbok Sandstone outcrops in the Project area and thickens to the southwest, it is generally unsaturated. However, it will become saturated where these sediments extend below the regional water table.

Recharge occurs via direct and diffuse rainfall to the Tertiary and Quaternary sediments. A small portion of the rainfall infiltrates down to the water table then moves through the system following the hydraulic gradient. Recharge to the Walloon Coal Measures will occur where the unit subcrops below the Springbok Sandstone, Tertiary sediments, or Quaternary alluvium.

The groundwater flow direction in the Walloon Coal Measures is towards the southwest. Groundwater inflows and seepage to the existing operation are negligible (AGE, 2015). However, as mining extends down dip, passive drainage towards the mining area will increase and the current zone of depressurisation around the mining area will expand. The southern part of the Project area has been extensively drilled with CSG wells, and the extraction of CSG and associated water will significantly alter the local hydraulic gradient in the Walloon Coal Measures (OGIA, 2016).

The QGC CSG production has resulted in significant depressurisation in the Walloon Coal Measures within and down gradient of the Project area. The sandstone and siltstone interburden and overburden of the Walloon Coal Measures form a confining aquitard over the floor and roof of the depressurised coal seams such that drawdown in the overlying Springbok Sandstone, attributable to CSG production south of the Project area is minimal (OGIA, 2016). On this basis, the overall low permeability of the interburden and overburden of the Walloon Coal Measures will have minimised depressurisation from the existing and approved mining at Cameby Downs Mine.

Groundwater quality in the Walloon Coal Measures is highly variable ranging from brackish to highly saline, and is generally unsuitable for stock watering.

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Rainfall

Tertiary CSG wells Quaternary Evaporation Sediments Alluvium 350 Columboola Evaporation Creek Evaporation Evaporation Recharge along Localised Surface runoff coal seam outcrop discharge to pit

able Water t 300 Elevation (metres AHD) Elevation (metres AHD) Elevation (metres AHD) W a mb o Condamine River (10km, 285 mAHD) Hor M izon ac alis ter Regional groundwater Ho ri K flow direction zon og an Hor izon Kumbarilla Beds Walloon Coal Measures (Springbok Sandstone)

250 0 5000 10000 15000 20000 Distance (metres)

Schematic showing conceptual groundwater model Figure 7.1 Groundwater Impact Assessment - Cameby Downs (G1831)

8 Environmental value of groundwater

The EPP Water (Section 2.2.1) provides a framework to protect and / or enhance the environmental values and hence suitability of Queensland waters (including groundwater) for various beneficial uses. Groundwater resources within the Project area lie within the Condamine and Balonne water resource plan which is part of the Murray-Darling and Bulloo Basins. A subordinate document to the EPP Water which will provide the Environmental Values (EVs) and Water Quality Objectives (WQOs) for the Murray-Darling Basin is under development and the Condamine and Balonne sub-basin is not listed in Schedule 1 of the EPP Water, therefore the environmental values relevant to the Project, as outlined in Part 3, Section 6(2) of the EPP Water, include:  aquatic ecosystem;  aquaculture and aquatic foods for human consumption;  agricultural purposes;  recreational purposes;  drinking water;  industrial purposes; and  cultural and spiritual values.

The EPP Water provides general WQOs to support and protect the various EV identified for waters. The WQO are long-term goals for water quality management. Each of the EV listed above are discussed below to identify those that are relevant to the Project.

Draft environmental values established for the Condamine catchment have since been prepared by the Condamine Alliance (2017). These are currently in draft form for comment, and are a recommendation to support their finalisation in the EPP Water and include environmental values for:  stock watering within areas that have >75% grazing use for the Northern Alluvia sub-aquifer, and  agriculture, aquaculture, drinking water, stock watering and industrial purposes for the Walloon Coal Measures sub-aquifer. Draft documentation has been released by the DES in 2018 and is currently the subject of final consultation under the Environmental Protection (Water) Policy 2009 on the EVs, aquatic ecosystem protection mapping and WQOs for all surface water and groundwater of the Queensland Murray- Darling Basin (QMDB). As these draft EVs, mapping and WQOs are yet to be finalised, no further consideration is made in this report.

8.1 Aquatic ecosystem As discussed in Section 6.10, there are no known springs or seeps within the Project area and no GDEs have been identified in field studies within the Project area (AGE 2013). The nearest mapped spring is associated with Wambo Creek approximately 3.2 km upstream of the confluence with Condamine River, and 23 km south of the mining lease boundary

Groundwater flow within the underlying aquifers is towards the southwest becoming deeper and confined as is moves further from the Project area. Groundwater levels are generally in excess of 35 m below ground surface and separated from surface waters, limiting potential to support GDEs. There are no springs from these deep confined aquifers within the Project area or surrounds that would support GDEs.

8.2 Aquaculture and aquatic foods for human consumption Groundwater is not used for aquaculture within (and neighbouring) the Project area.

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8.3 Agricultural purposes As discussed in Section 6.9.3, there is no significant groundwater usage within (and neighbouring) the Project area. The primary agricultural purpose of land within and surrounding the Project area has been low intensity cattle grazing. No known irrigation bores are located within 10 km of the Project area.

Without site specific WQO, the EPP Water refers to the livestock drinking water guidelines presented in ANZECC (2000). Table 8.1 presents the tolerance of livestock (beef cattle) to TDS in drinking water. The groundwater quality data for the site monitoring bores identifies this water would be unsuitable for stock watering based on the naturally elevated TDS levels (refer Section 6.7).

Table 8.1 Tolerance of livestock (beef cattle) to TDS in drinking water

Animals may have initial reluctance to Loss of production and decline in animal No adverse effects on drink or there may be some scouring, condition and health would be expected. animals expected but stock should adapt without loss of Stock may tolerate these levels for short production periods if introduced gradually

0 – 4,000 mg/L 4,000 mg/L – 5,000 mg/L 5,000 mg/L – 10,000 mg/L

Guidelines for trace metal concentrations in livestock (beef cattle) drinking water are provided by ANZECC (2000), these are summarised in Table 8.2. Water quality data for dissolved metals reported for the Project monitoring bores (Appendix B) is below these guideline levels.

Table 8.2 Livestock (cattle) drinking guidelines (ANZECC, 2000)

Trigger value Element (low risk)1 (mg/L)

Aluminium 5

Arsenic 0.5

Boron 5

Cadmium 0.01

Chromium 1

Cobalt 1

Copper 1

Fluoride 2

Lead 0.1

Mercury 0.002

Molybdenum 0.15

Nickel 1

Selenium 0.02

Uranium 0.2

Zinc 20

Notes: 1) Higher concentrations may be tolerated in some situations (details provided in AWQG, Volume 3, Section 9.3.5). Metal values relate to the total concentration of the constituent.

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8.4 Recreation

Groundwater is not used for recreational purposes within (and neighbouring) the Project area.

8.5 Drinking water

Data indicates that groundwater quality in the Project area is brackish to saline and not suitable for human consumption.

8.6 Industrial purposes

The Project will recycle groundwater that seeps into the open cut pit. The water will be pumped to holding dams, where it will be incorporated into the mine water balance.

The EPP Water does not specify a suite of parameters that are applicable for industrial use. Whilst ANZECC (2000) does not provide guidelines to protect industries, it indicates that industrial water quality requirements need to be considered on a case-by-case basis. Based on this approach, groundwater accessed by the Project would provide a beneficial industrial use.

8.7 Cultural and spiritual values

There are no known environmental values in relation to cultural and spiritual values of groundwater within the Project area.

8.8 Conclusion

In the absence of any site specific WQO’s currently available, review of the draft environmental values established for the Condamine catchment identifies that the (regional) groundwater quality for the Walloon Coal Measures sub-aquifer is unlikely to be suitable/used for agriculture, aquiculture, stock or domestic purposes post mine closure. That is, the elevated groundwater salinity essentially precludes its use for these purposes.

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9 Impact assessment

9.1 Introduction

The proposed activities have the potential to impact on the groundwater regime of the region through extraction of coal by open cut mining methods. This mining will result in the depressurisation of the surrounding strata. Based upon the Project mine plan and the assessment of the existing groundwater setting, the potential groundwater impacts associated with the Project are as follows:  groundwater inflow to the pit from the surrounding aquifer, and the extent these flows might have on groundwater levels in the wider aquifers and groundwater users of this aquifer;  changes in groundwater levels as a result of groundwater inflow to pits;  cumulative impacts with the CSG operations; and  post-mining impacts on groundwater regime.

This section provides a detailed assessment of these potential impacts and is structured as follows:  Section 9.2 provides a summary of previous numerical modelling and predicted impacts of the Cameby Downs Mine operations.  Section 9.3 provides an overview of the proposed open cut mining activities which provides the basis for groundwater numerical model developed to assess the impact of mining. Appendix E provides a detailed technical description of the model development, construction and calibration.  Section 9.4 describes potential impacts to groundwater users and the environment.  Section 9.5 outlines potential cumulative impacts from the Project and nearby CSG production.

9.2 Summary of approved mining impacts for the Cameby Downs Mine

In 2006, AGE completed a GIA for the now approved Cameby Downs Mine (AGE, 2006). The mine was proposed with a 31 year mine life at an annual extraction rate of approximately 1.3 Mtpa.

Predictive modelling was undertaken of the progression of the mine over the 31-year mine life using FEFLOW. The simulations were undertaken using a monthly time step to provide data on the magnitude of groundwater inflow to the mine workings. At the time the model was developed, CSG operations had not commenced within the region. Therefore, cumulative impacts due to CSG were not accounted for within the approved groundwater impact predictions.

Groundwater inflow into the mining area was dependent upon the location of the active mining area and ranged from zero, where the coal seams occur above the regional water table and 0.089 ML/day at the deepest mined part of the coal seams. Groundwater drawdown at the end of mining was simulated to extend approximately 2 km (Figure 9.1). The total extent of drawdown in a northwest or southeast direction was up to 1 km.

The findings of the study indicated that no alluvial aquifers, springs, GDEs or existing groundwater users would be adversely impacted by the mining operations. Hence no mitigation measures were necessary.

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After cessation of mining, a pit lake would start to develop in the final void. As the pit void would remain a permanent groundwater sink, the area of drawdown in the groundwater table continued to increase until steady-state conditions prevail, whereby groundwater flow to the void was balanced by recharge. The simulated drawdown 100 years after mining is shown in Figure 9.2. The figure shows that the extent of groundwater drawdown developed with time due to the permanent groundwater sink created by the pit void. The direction of greatest drawdown was generally in a south-westerly direction, and after 100 years extended approximately 5.3 km from the mine.

The closest registered bore (RN10725) was located approximately 5.7 km southwest of the mine in the direction of the greatest drawdown. This bore was assessed to not be constructed in the same aquifer as the mine, and as such, no impacts post mining were expected.

The quasi-steady state water level in the final pit void was predicted to be approximately 290 m AHD and occurred in excess of 200 years post mining. This water level was some 15 m below the pre-mining water level of 305 mAHD, indicating that the pit void would remain a long term groundwater sink. The modelling predicted that the groundwater inflow to the final pit void is initially quite high, but stabilises with time due to the balance of groundwater and waste rock leakage inflow and evaporation at a rate of about 0.4 ML/day.

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Figure 9.1 Approved drawdown extent in Walloon Coal Measures – end of mining (AGE, 2006)

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Figure 9.2 Approved drawdown extent in Walloon Coal Measures – 100 years post mining (AGE, 2006)

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Mining at Cameby Downs Mine commenced in 2010, and the groundwater model was also updated to MODFLOW SURFACT to assess the impacts of a proposed expansion to activities at the mine (AGE, 2010). In 2013, the model was amended and re-calibrated to address a change in the mine plan (AGE, 2013). The model was subsequently used to verify the previous model predictions (AGE, 2015). As part of the process, AGE utilised the updated version of the model that was developed in MODFLOW-SURFACT, which predicted pit seepage from 2010 to 2015 in the order of 0.05 ML/day to 0.4 ML/day. These predictions were higher than those predicted by AGE (2006), largely due to changes in recharge parameters and the model verification. Additionally, these predicted inflows did not account for losses due to evaporation, which was assessed to be 2.7 times higher than rainfall (AGE, 2015).

On this basis, evaporation over the area and depth of mine excavation would remove this predicted seepage prior to triggering pumping requirements. This concept is consistent with the generally dry mining conditions experienced at the Cameby Downs Mine. As such, it was assessed that the overall predicted inflows were very low, which aligned with the initial 2006 model predictions and site observations.

The extent of drawdown as shown by the 1 m contour was assessed to extend approximately 2.5 km to the southwest from the highwall, 1 km to the northwest and 2 km to the southeast from the open pit as shown in Figure 9.3. The simulated drawdown contours provided a good match with the observed data measured in the observation bores.

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Figure 9.3 Predicted drawdown extent for 2015 (AGE, 2015)

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9.3 Overview of groundwater modelling for the Project

9.3.1 Proposed mine plan

The Project involves extension of open cut mining operations within ML 50233 and into MLAs 50258, 50259, 50260 and 50269 (Figure 1.2) at an increased mining rate of 3.5 Mtpa, for a period of approximately 75 years. The extension to the approved open cut operation for the Project provides for mining progressing in a south westerly direction as shown in the mine plan presented in Figure 9.4.

Open cut mining will result in progressive depressurisation of the surrounding strata and subsequent recovery post mining. Appendix E describes how the groundwater model simulated the proposed mining.

A 3D numerical groundwater flow model was developed for the Project based on historic models developed for the approved operations. As discussed in Section 9.2, the model review by AGE in 2015 concluded that the current model was fit for purpose and verified well against the observed data and site observations. The model was updated to include the proposed mine plan as well as other updates to align the model with more contemporary modelling practices. This is detailed further in Appendix E.

The model represents the key geological units as three layers, and is aligned in a general north- easterly direction. The model extended approximately 35 km from northwest to southeast, and 23 km from northeast to southwest comprising up to 102,400 cells per layer. The model was developed around the conceptual groundwater model summarised in Section 7, and is detailed in Appendix E.

The model was calibrated and verified to existing groundwater levels, using reliable measurements from representative bores within the model domain. A detailed description of the calibration method is provided in Appendix E. The objective of the calibration was to replicate the observed groundwater levels in accordance with the modelling guidelines developed by Barnett et al., (2012). The transient calibration achieved an 8.9 % scaled root mean square (SRMS) error, which is less than the 10 % SRMS error suggested by the modelling guidelines as constituting a calibrated model. Comparison of the predicted and observed hydrographs shows a good qualitative match in groundwater level trends.

Once calibrated, the model was used to predict the groundwater level response to the Project, including simulated mining of the open cut pit in accordance with the proposed mine plan. The model simulated mining to the base of the Walloon Coal Measures, defined as layer 2 in the groundwater model.

The sensitivity of the model predictions to the input parameters was tested and analysed. The analysis included varying model parameters and design features that could most influence the model predictions. The model parameters were adjusted to encompass the range of likely uncertainty in key parameters. Sensitivity analysis included testing the effects of changes in:  horizontal and vertical hydraulic conductivity, specific yield, and specific storage for all geological units; and  the rainfall recharge rate across the model domain and overburden.

Appendix E provides a detailed discussion of the sensitivity analyses undertaken. The following sections describe the predictions of the groundwater model.

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9.4 Groundwater modelling predictions

9.4.1 Groundwater inflow to mining areas

The transient development of the mine was simulated on a quarterly basis for 80 years between 2010 and 2090 . The proposed mine plan for the Project provides for a mining progression within three distinct areas referred hereafter as the central, eastern and western mining areas. The pit inflows determined from the predictive simulation for each mining area are shown graphically in Figure 9.5. These predicted inflows represent seepage reporting to the open cut pits over the proposed mine operations for the Project.

The magnitude of groundwater inflow is function of the size of the open cut pit, position of the mine relative to the depth of the coal seams and the size of the previously mined areas. Groundwater inflow is very low when mining occurs near the sub-crop area in the north / northeast of the model area. This is due to the base of workings in this area being close to the natural groundwater table, and when this area becomes partially dewatered from previous mining of adjacent strips, the local hydraulic gradients are low.

The predicted inflow into the open cut pits increases as the mine develops and advances in a down-dip direction (Figure 9.5). Predicted inflows to the open cut pits show some variability and inflows tend to be greatest when the open cut pit extends into areas where groundwater has not already been significantly depressurised by mining. As a result of this process, increased groundwater inflow is evident in Years 2042-2044, 2062-2063 and 2087-2089. The average predicted pit inflow rate is 0.51 ML/day (188 ML/year), but ranges between 0.21 ML/day and 0.97 ML/day (76 ML/year and 355 ML/year).

These predictions are considered low despite including a component of inflow from the waste rock located within areas already mined. The inflows from these different sources have not been separated, and the results are considered conservative.

Figure 9.5 Predicted average annual pit inflows

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Table 9.1 presents the predicted additional groundwater extraction as seepage reporting to the respective open pits for both the approved and proposed mine plans for each mining year between 2018 to 2090.

Table 9.1 Predicted groundwater extraction – 2018 to 2090

Predicted additional groundwater extraction Total predicted (ML/year) groundwater Calendar year extraction Eastern mining Central mining Western mining area area – Pit 2 area – Pit 1 – Pit 3 (ML/year)

2018 0 108 0 108

2019 0 203 0 203

2020 0 115 0 115

2021 0 128 0 128

2022 0 142 0 142

2023 0 141 0 141

2024 0 148 0 148

2025 0 154 0 154

2026 0 159 0 159

2027 0 155 0 155

2028 0 158 0 158

2029 0 166 0 166

2030 0 175 0 175

2031 0 180 0 180

2032 0 188 0 188

2033 0 192 0 192

2034 0 194 0 194

2035 0 202 0 202

2036 0 210 0 210

2037 0 211 0 211

2038 0 208 0 208

2039 0 208 0 208

2040 0 255 0 255

2041 0 214 0 214

2042 60 177 0 237

2043 151 150 0 301

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Predicted additional groundwater extraction Total predicted (ML/year) groundwater Calendar year extraction Eastern mining Central mining Western mining area area – Pit 2 area – Pit 1 – Pit 3 (ML/year)

2044 161 144 0 305

2045 145 144 0 289

2046 124 107 0 232

2047 130 64 0 194

2048 148 68 0 216

2049 152 70 0 222

2050 148 72 0 220

2051 134 73 0 208

2052 124 74 0 198

2053 118 75 0 193

2054 114 75 0 189

2055 138 75 0 213

2056 161 74 0 236

2057 172 73 0 245

2058 125 72 2 199

2059 110 70 17 198

2060 98 70 42 210

2061 76 69 51 196

2062 38 69 63 169

2063 1 68 201 270

2064 1 68 58 127

2065 1 68 44 113

2066 1 68 36 105

2067 1 68 37 106

2068 1 68 31 101

2069 1 68 8 77

2070 1 68 7 76

2071 1 68 8 77

2072 1 68 14 83

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Predicted additional groundwater extraction Total predicted (ML/year) groundwater Calendar year extraction Eastern mining Central mining Western mining area area – Pit 2 area – Pit 1 – Pit 3 (ML/year)

2073 1 68 23 93

2074 1 69 48 117

2075 1 69 73 143

2076 2 69 116 187

2077 1 69 129 200

2078 2 69 107 178

2079 12 70 96 177

2080 77 70 71 218

2081 75 70 65 210

2082 107 65 61 233

2083 119 46 60 225

2084 72 36 80 187

2085 68 35 105 208

2086 64 34 112 210

2087 54 34 123 211

2088 49 34 232 315

2089 51 34 270 355

2090 52 35 137 224

The predicted inflow rates presented in Figure 9.5 represent the take of water over the duration of the Project. Overall, the inflow rates are low which is in line with the inflow rates currently experienced at the mine. It is noted that a proportion of these predicted groundwater inflows may be lost as moisture in the coal (entrained water) and at times, from direct evaporation from the exposed coal seam. However, given the variability in the extent of coal seams exposed at any one time, highwall angle and height of exposed coal seams, in comparison to the surface area of the mine water storages to which the direct groundwater inflows would be pumped to, such losses are considered negligible for the purposes of this assessment. As the groundwater model inflow predictions are based on annual snapshots, such instantaneous losses are considered to be within the bounds of reasonable accuracy of the averaged groundwater model predicted inflow ranges.

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9.4.2 Drawdown and depressurisation during mining operations

Figure 9.6 and Figure 9.7 show the maximum zone of depressurisation due to the Project (proposed mine plan only) within the Kumbarilla Beds (layer 1) and Walloon Coal Measures (layer 2), respectively, up to the end of mining in 2090. These show that the drawdown extent within the Kumbarilla Beds is slightly less than that for the Walloon Coal Measures. This is not unexpected given the presence of lower permeability interburden strata (aquitards) between these geological units. As discussed in Section 7, the sandstone and siltstone interburden and overburden of the Walloon Coal Measures form a confining aquitard over the floor and roof of the depressurised coal seams.

The resultant zone of depressurisation in the Walloon Coal Measures coal seams for the Project is predicted to extend up to 5 km to the southwest of the Project. The extent of drawdown within the Walloon Coal Measures is constrained due to the structure of the coal measures, which outcrop north of the Project area and dip towards the southwest. This is greater than the 2 km drawdown extents predicted for the approved mine plan, and is a result of the larger mine plan extending further southwards and deeper within the Walloon Coal Measures.

The cumulative drawdown from both the approved and proposed mine plans is presented as a proportion (percentage) attributable to the proposed mine plan in Figure 9.8 and Figure 9.9 within the Kumbarilla Beds (layer 1) and Walloon Coal Measures (layer 2), respectively. This shows the proportion of drawdown attributable to the proposed mine plan (in excess of 50%) shaded in brown, and to the approved mine plan (in excess of 50%) shaded in purple. Where the drawdown extends within the Walloon Coal Measures to the:  northwest and southeast, this is between 80% and 100% attributable to the proposed mining operation; and  south and southwest, this is between 50% and 80% attributable to the proposed mining operation.

Where the drawdown is generally central to the northeast along the Walloon Coal Measure subcrop, this is between 80% and 100% attributable to the approved mining operation.

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9.4.3 Cumulative impacts

The numerical groundwater model was used to assess cumulative drawdown with CSG development which partially overlaps the Project area, therefore requiring consideration of the cumulative impact between the two projects. Associated groundwater is removed from the coal seams as a by-product of the CSG production, and this has resulted in significant depressurisation of the Walloon Coal Measures near the Project area. No other mining operations are within 10 km of the Project area.

Figure 9.10 to Figure 9.11 shows the maximum cumulative drawdown for the Kumbarilla Beds (layer 1) and Walloon Coal Measures (layer 2). Due to the history and extensive nature of CSG within the region, the maximum cumulative drawdown to the end of mining (in 2090) was determined by comparing these groundwater levels against the pre-mining groundwater levels (in 2010). As shown in Figure 9.10 and Figure 9.11, cumulative drawdown impacts extend across much of the model domain. As discussed in Section 3.2, the Project area is within the Walloon Coal Measures IAA and LAA and the southern extent is within the Springbok Sandstone LAA.

Figure 9.10 to Figure 9.11 also show the proportion (as a percentage) of the cumulative drawdown attributable to the approved mine plan (brown shading) compared to that for the CSG operations and the approved mine plan. Locally within the Project area the drawdown within the proposed mine plan footprint will be dominated by dewatering and depressurisation associated with proposed open cut pits. This is a function of the Project being located in shallower parts of the Walloon Coal Measures where it is not predicted to be subject to the deep drawdown reported in the UWIR (OGIA, 2016). That is, at the mine site the contribution from CSG is predicted to be less than 5 m of the 20 m to 50 m drawdown predicted within the mine footprint. Regionally, the cumulative predicted drawdown for both the Kumbarilla Beds and Walloon Coal Measures extend towards the southeastern, southern and western model boundaries, where they are dominated (up to 100%) by the CSG operations.

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9.4.4 Water licensing

Under the Water Act (current at 1 March 2017), the Project will require an associated water licence for this EA amendment application. The purpose of an associated water licence is provided in Section 1250C, Division 2 of the Water Act which states “An associated water licence authorises the taking of or interference with underground water in the area of a mining tenure if the taking or interference happens during the course of, or results from, the carrying out of an authorised activity for the tenure.”

9.4.5 Impacts on groundwater users

As discussed in Section 9.4.2, the depressurised zone as a result of the Project in the Walloon Coal Measures extends a maximum 5 km towards the southwest of the Project area. In contrast, cumulative drawdown impacts attributable principally (up to 100%) to CSG impacts extend across much of the model domain.

Figure 9.12 shows the locations of the registered bores identified in the DNRME GWDB in relation to the zone of depressurisation. Only two existing registered bores on the DNRME GWDB are identified within the predicted zone of depressurisation. These are RN168040 and RN168041, which are the Cameby Mine monitoring bores CD036R and CD018 (respectively). No landholder water supply bores are located within the predicted drawdown extents attributable to the proposed mine plan for the Project.

It is important to note that a conservative approach has been adopted in the modelling, and the zone of influence is not expected to develop to the full extent predicted by the numerical modelling for the following reasons:  The model does not include any hydraulic heterogeneities in the area and simulates a continuous hydraulically connected aquifer system. Minor faults offset the coal seams and heterogeneities can act as barriers to groundwater flow, which limits the expansion of the zone of depressurisation.  The model assumes the entire mine footprint will be dewatered down to the WM3 seam, which would overestimate the cone of depression and the area of influence.

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9.4.6 Impacts on groundwater dependent ecosystems

The Project is not predicted to impact any aquatic or terrestrial GDEs since GDEs are assessed as being unlikely to occur within and surrounding the Project area (Section 6.10). There is a potential for thin, discontinuous and temporal alluvial aquifers to occur (which may be used by localised areas of terrestrial vegetation). However, these would consist of a perched groundwater system hydraulically separated from the underlying Walloon Coal Measures by the very low permeability overburden (comprising the Springbok Sandstone and the upper Walloon Coal Measures). Therefore, it is assessed that there will be no impact from mining on localised shallow alluvial or perched aquifers or any GDEs that may be associated with these groundwater systems.

The presence of stygofauna in groundwater within the Project area was assessed by Ecowise Environmental in February 2010 who sampled seven monitoring bores. Ecowise found no stygofauna in any samples and concluded that “the absence of stygofauna and the high EC suggest that there is unlikely to be a large stygofauna community at Cameby Downs”.

9.4.7 Impacts on environmental values

As discussed in Section 8, there are two EV outlined in the EPP Water relevant to the Project, which include:  agricultural purposes, including livestock and cattle grazing; and  industrial purposes.

The primary agricultural purpose of land within and surrounding the Project area has been for low intensity cattle grazing. As discussed in Section 9.5.1 the predicted void levels are below pre-mining groundwater levels, and will therefore act as a sink to groundwater flow. Any increase in salinity due to the Project (as a result of evaporation, or from acid generation of rejects or overburden material) will be contained within the final void.

The Project will recycle groundwater that seeps into the open cut pit. The water will be pumped to holding dams, where it will be incorporated into the mine water balance. Therefore the Project would provide a beneficial industrial use by supplying water for the Project.

9.5 Post mining recovery conditions

Post mining conditions were also simulated using the numerical groundwater flow model. The location of the final voids are shown in Figure 9.4 and Appendix E provides details of the model set up.

The sections below describe the post mining predictions of the pit lake levels, potentiometric surface and water table recovery, and water quality variation. These predictions are based on the currently approved mine and CSG activities and the Project related development.

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9.5.1 Post closure groundwater recovery

Post closure conditions were simulated over a period of 500 years by WRM Pty Ltd (WRM) to predict the extent of void lake level recovery following cessation of mining. Their predictions indicate the two voids will remain as groundwater sinks with void water levels remaining below pre-mining groundwater level. The equilibrated void water levels were used to determine the longterm residual drawdown in the surrounding aquifers (Kumbarilla and Walloon Coal Measures). This was achieved in a steady state simulation using the WRM predicted equilibrium water levels in each void.

Based on this final landform, two final voids (Central Void and Western Void, refer Figure 9.4) are proposed as part of the Project.

The WRM modelling indicates that the final voids will gradually fill over time from direct rainfall occurring across each void and groundwater seepage. The final voids are predicted to reach pit lake levels of approximately 280 mAHD in Central Void and 285 mAHD in Western Void. These pit lake water levels are predicted to be between 20 m (Western Void) and 25 m (Central Void) below the pre- mining groundwater levels. Based on these predictions, the voids will act as sinks in perpetuity with no escape of contained void water into the Walloon Coal Measures.

A new equilibrium groundwater level would be established around the final voids. Figure 9.13 and Figure 9.14 show the predicted extent and magnitude of post mining drawdown in the Kumbarilla Beds (layer 1) and Walloon Coal Measures (layer 2), respectively.

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9.5.2 Jurassic groundwater intercepted post mining

The modelling indicates the final voids will gradually fill with water over time. The model predicts final pit lake levels for the two voids ranging between approximately 280 mAHD and 285 mAHD. As the predicted pit lake levels are below pre-mining groundwater levels, the voids will act as a sink and will have a long term ‘water take’.

The Project is predicted to intercept approximately 0.17 ML/day (63 ML/year) of groundwater inflow to the final voids at equilibrium conditions. This is due to evaporative losses from the groundwater filled voids resulting in each void remaining a permanent groundwater sink post mine closure.

9.6 Impacts on groundwater quality

This section describes the potential sources of groundwater quality changes associated with the Project.

9.6.1 Overburden emplacement areas and final void lakes

Although the majority of overburden could be managed as non-acid forming material, carbonaceous units in the overburden may have a capacity to generate acid (SRK Consulting, 2012). Overburden will continue to be placed within the open cut pits and progressively rehabilitated during mining. Under the Project, surface water runoff and accumulated rainfall seepage will drain towards the voids. Similarly, groundwater will also be drawn in from the surrounding geological units towards the voids. Evaporation from the void lake surfaces will maintain a water level below the surrounding aquifer water levels, forming a groundwater sink in the local environment. Evaporation from the lake surfaces will also slowly concentrate salts in the pit lake over time. The increasing salinity will not pose a risk to other aquifers and surface water features as the final void will remain a permanent sink.

9.6.2 Hydrocarbons

There is limited potential for groundwater contamination to occur as a result of hydrocarbon and chemical contamination with provision for immediate clean-up of spills. All chemicals will be transported, handled and stored in accordance with relevant Australian Standards. These controls represent standard practice and a legislated requirement at mine sites for preventing the contamination.

9.6.3 Coal rejects storage

Coarse rejects generated at the Cameby Downs Mine were initially co-disposed with fine rejects in the out-of-pit coal rejects emplacement located within the rail loop. In early 2017, dry coarse rejects began to be disposed of in-pit and encapsulated with waste rock.

Coarse rejects would continue to be disposed in-pit and encapsulated with waste rock over the Project life.

Fine rejects are currently pumped to the out-of-pit coal rejects emplacement located within the rail loop. Water from the fine rejects stream is decanted and returned to the site water management system for re-use. As each of the three cells is filled, they are allowed to dry prior to being capped with an inert waste rock material, topsoiled and rehabilitated.

Fine rejects generated at the Project would either continue to be pumped to out-of-pit coal rejects emplacements or placed in, in-pit coal rejects emplacements. This would include construction of a new out-of-pit (Rejects Dams, RD2) and multiple in-pit (within Central Void) coal rejects emplacements over the Project life.

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Coal rejects will need to be managed to control formation and release of any acid drainage (SRK Consulting, 2012). The strategies for managing rejects placement are described in the Reject Management Concept Design Report (Engeny, 2018) This includes placement of coarse and fine reject materials in Integrated Waste Landform (IWL) cells located hydraulically up-gradient of the final Central void. This will result in any seepage from the emplaced rejects reporting to the final Central void. As the final voids are predicted to become sinks, any resultant seepage from the emplaced rejects will be captured and contained within the final voids.

As detailed in Section 9.5.1, it is predicted that the final voids for the Project will recover to a quasi-equilibrium level between 280 mAHD and 285 mAHD, which is approximately 20 m to 25 m below pre-mining groundwater levels. As a result, it is predicted that the final voids will act as sinks to groundwater flow. Any poor quality water within the in-pit rejects emplacement will be captured in the final pit void lakes. Evaporation from the final pit voids will concentrate salts slowly over time. Therefore, there will be little potential for interaction of pit void water with other aquifers or surface water features.

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10 EPBC Act Significant Impact on Water Resources Guidelines

In December 2013, the Federal Department of Environment and Energy (DotE) released guidelines for proponents of CSG and large coal mining projects to assess the potential for significant impacts on water resources (DotE, 2013). The guideline outlines a ‘self-assessment’ process that assists proponents to identify if their project is likely to have a significant impact on water resources.

This report considers the impact of the Project on groundwater resources, and if these impacts are significant according to the guidelines. It compares the predicted impacts against the DotE guidelines to determine if the Project could have a significant impact on water resources. It also considers the potential for cumulative impacts with other developments.

The guidelines indicate that the Project must have ‘a real or not remote chance or possibility that it will directly or indirectly result in a change to’ the ‘hydrology’ or ‘water quality’ of the water resource. This change must be of ‘sufficient scale or intensity as to reduce the current or future utility of the water resource for third party users’. Third party users can include ‘environmental and other public benefit outcomes, or to create a material risk of such reduction in utility occurring’. Furthermore, ‘Whether or not an action is likely to have a significant impact depends upon the sensitivity, value, and quality of the water resource which is impacted, and upon the intensity, duration, magnitude and geographic extent of the impacts’.

A summary of the IESC guidelines and where they are addressed within the report is included in Appendix A.

10.1 Water availability to users

Two existing registered bores are present within the zone of drawdown predicted by the model (Section 9.4.5). These are Cameby Mine monitoring bores that are located within the mining area. No landholder water supply bores are located within the predicted drawdown extents attributable to the proposed mine plan for the Project. This is due to the aquifers being either unsaturated or partially unsaturated in the vicinity of the Cameby Downs Mine (as is the case with the Springbok Formation within the Kumbarilla Beds), or saline as is the case with the Walloon Coal Measures.

10.2 Water availability to the environment

There are no watercourses with associated alluvial aquifers within the Project area, and based on the site geology, it is assessed unlikely there are any alluvial aquifers within the modelled area. Whilst it is acknowledged that minor areas of alluvial aquifers may be associated with Columboola Creek, if present, these would consist of thin, discontinuous, temporal or perched groundwater systems separated from the underlying Walloon Coal Measures by the very low permeability overburden. Therefore, it is assessed that there will be no impact from mining on localised shallow alluvial or perched aquifers and GDEs that may be associated with these aquifer systems.

10.3 Water quality

It is proposed to emplace coarse and fine reject materials in later years, into the mined-out voids (i.e., within Central Void). Modelling predicts that the water levels within the final pit voids would recover to a quasi-equilibrium level of between 280 mAHD and 285 mAHD for the proposed final voids. This level is approximately 20 m to 25 m below the pre-mining groundwater level and means that the final pit voids will act as sinks to groundwater flow, preventing flow of water back into the surrounding groundwater systems. Therefore any increased groundwater salinity from the in-pit emplacement of overburden and rejects material will be contained within the pits.

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10.4 Cumulative impacts

Cumulative impacts in the region of the Project extend across much of the model domain, and are solely due to impacts from CSG development, which partially overlaps with the Project area. Logically the drawdown that is attributable to the Project is adjacent to the open cut pits, with the influence reducing with distance from the Project area. Section 3.2 identifies the Project area is within the Walloon Coal Measures IAA and LAA and the southern extent is within the Springbok Sandstone LAA (OGIA, 2016). As such, this assessment indicates the Project will only add a small to moderate ‘water take’ that is predicted to be comparatively low compared to the already approved impacts from CSG operations.

That is, beyond the existing and approved impacts associated with the Cameby Downs Mine and the surrounding gas development projects, the Project is therefore assessed to be:  unlikely to directly or indirectly result in a substantial change in the hydrology of the groundwater resources; and  unlikely to directly or indirectly result in a substantial change in water quality of water resources.

10.5 Avoidance or mitigation measures

The mine plan does not intersect any existing alluvial aquifers or watercourses. It does however, intersect mapped drainage features within the Project area, which are ephemeral and only flow during, and shortly after heavy rainfall events. Similarly, the impacts that occur through the depressurisation of the underlying Walloon Coal Measures do not extend and impact upon any the alluvial aquifer and connected streams associated with the Condamine River. The Condamine River is located 17 km to the south of the Project area.

Groundwater seepage and inflow to the mine areas cannot be prevented, and must be removed to ensure safe operating conditions. Whilst not predicted to occur, should the Project be demonstrated to affect any private groundwater user possessing a water supply, make-good measures with affected land owners would likely include:  ensuring the bore owner has access to a similar quantity and quality of water for the water bore’s authorised purpose for example by: o bore enhancement by deepening the bore or improving its pumping capacity; o constructing a new water bore; or o providing a supply of an equivalent amount of water of a suitable quality by piping it from an alternative source.

However, such make good agreements would be unlikely to be required as no landholder bores are predicted to be impacted by the Project.

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10.6 Conclusion

Groundwater within the Springbok Sandstone and Walloon Coal Measures surrounding the Project is used sparingly by surrounding landholders of which there are no water supply bores located within the predicted zone of impact from the Project (refer Section 9.4.5). Similarly, this groundwater resource is assessed to not be hydraulically connected with any creeks. As such, any impact from mining on nearby creeks is highly unlikely, and the project is not assessed to impact any mapped groundwater dependent ecosystems.

In summary, the mining induced zone of depressurisation in the target coal seams that hosts poor quality, saline groundwater would not be considered a significant impact as there are no consequences resulting from the depressurisation.

Comparison of the potential impacts against the DotE (2013) guidelines concludes that the Project is not likely to have a significant impact on this groundwater resource.

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11 Groundwater monitoring strategy / program

This section of the report provides a recommended groundwater monitoring program that will provide both an on-going assessment of the impact of the Project and a proactive indicator of any adverse impacts on the groundwater regime.

11.1 Monitoring bore network

The proponent currently maintains a groundwater monitoring program for the approved mining operations in accordance with EA (EPML00900113). With the updates to the mine plan, all site monitoring bores will be destroyed over the life of the Project. The existing bores will provide a good indication of groundwater response to mining and should be monitored while they are accessible. Installation of additional bores (MB1 to MB12) is proposed to monitor groundwater levels and water quality down gradient of:  the eastern, central and western mining areas (MB1 to MB5);  Central and Western final voids (MB6, MB7 and MB9); and  the Central void in-pit reject placement area (MB8A/MB8B) and out of pit reject placement area within the rail loop and rejects dam areas (MB10A/10B to MB12A/12B).

The monitoring bores MB1 to MB8A, and MB9 should be developed to target groundwater associated with the deepest coal seams proposed to be mined in these areas, namely the upper Macalister Horizon (MA1) down to the lower Wambo Horizon (WM3). Monitoring bore MB8B is a proposed shallow bore (approximately 25 m to 30 m depth) planned to intersect the potential for shallow seepage within the weathered geology downgradient of the Central void in-pit reject placement area.

Paired/nested monitoring bores (MB10A/10B to MB12A/12B) are planned to intersect the potential for shallow seepage downgradient from the out of pit rejects placement facilities within the rail loop and rejects dam areas. Bores MB10A, MB11A and MB12A are deeper monitoring bores (between 15 m and 30 m depth) planned to intersect seepage into groundwater potentially associated with the base of weathering. Bores MB10B, MB11B and MB12B are shallow monitoring bores (between 5 m and 10 m depth) planned to intersect potential shallow groundwater seepage within the regolith.

Where the alluvial aquifer is present, a nested bore would be placed in this shallow-most monitoring zone.

The installation of these additional bores will serve to capture additional baseline groundwater monitoring prior to the existing monitoring bores being destroyed by mining. To facilitate this groundwater monitoring objective, the new monitoring bores should be installed within six months of the EA amendment being approved to ensure the baseline data is collected prior to mine operations commencing in that area. This will effectively allow continuation of monitoring impacts from the project when the existing monitoring bores are destroyed by mining.

Details of the existing and proposed groundwater monitoring network are provided in Table 11.1 with their locations shown in Figure 11.1.

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Table 11.1 Proposed Cameby Downs monitoring network

Surface Screened Recommended Bore ID Easting Northing elevation interval Target unit monitoring (mAHD) (mbGL)

Existing mine groundwater monitoring bores

SWL: monthly* CD018 237983 7049824 322.1 41.5 - 47.5 MA1 / MA2 coal seams Quality: yearly

SWL: monthly * CD034C 235706 7054194 350.6 34.9 - 46.9 MA1 / MA2 coal seams Quality: yearly

SWL: monthly * CD036R 235094 7052931 338.6 39.4 - 47.4 MA1 / MA2 coal seams Quality: yearly

SWL: monthly * CD037C 235563 7053320 346.1 39.5 - 47.5 MA1 / MA2 coal seams Quality: yearly

SWL: monthly * CD056 236505 7051782 328.2 53.2 - 59.2 MA1 / MA2 coal seams Quality: yearly

SWL: monthly * CD065 235953 7053638 343.6 27 – 33 MA1 / MA2 coal seams Quality: yearly

Additional mine groundwater monitoring bores

SWL: monthly * MB1# 231795 7054211 ~345.2 ~60 - 69 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB2# 233210 7051935 ~339.2 ~124 - 132 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB3# 234286 7048018 ~331.2 ~124 - 132 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB4# 238220 7046855 ~317.5 ~89 - 97 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB5# 240000 7048670 ~321.2 ~66 - 74 MA1-WM3 coal seams Quality: quarterly

Additional mine void groundwater monitoring bores

SWL: monthly * MB6# 232722 7053076 ~343.8 ~100-108 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB7# 234523 7052280 ~333.4 ~78-86 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB8A# 235073 7050049 ~330.7 ~99-107 MA1-WM3 coal seams Quality: quarterly

SWL: monthly * MB8B# 235073 7050049 ~330.7 ~25-30 Base of weathering Quality: quarterly

SWL: monthly * MB9# 236930 7048570 ~321.1 ~96-104 MA1-WM3 coal seams Quality: quarterly

Additional out of pit rejects disposal groundwater monitoring bores

SWL: monthly * MB10A# 234839 7048299 ~326.7 ~15-30 Base of weathering Quality: quarterly

SWL: monthly * MB10B# 234839 7048299 ~326.7 ~5-10 Base of regolith Quality: quarterly

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Surface Screened Recommended Bore ID Easting Northing elevation interval Target unit monitoring (mAHD) (mbGL)

SWL: monthly * MB11A# 235490 7047679 ~322.8 ~15-30 Base of weathering Quality: quarterly

SWL: monthly * MB11B# 235490 7047679 ~322.8 ~5-10 Base of regolith Quality: quarterly

SWL: monthly * MB12A# 236450 7048040 ~321.5 ~15-30 Base of weathering Quality: quarterly

SWL: monthly * MB12B# 236450 7048040 ~321.5 ~5-10 Base of regolith Quality: quarterly

Notes: Coordinates in GDA94Z56 * recommend installation of a datalogger set to record water levels 6 hourly, in addition to manual monthly water level measurements in each monitoring bore, or as otherwise agreed by DES # proposed monitoring bore to replace existing bores prior to removal by mining

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11.2 Water level monitoring plan It is recommended that groundwater level monitoring is initially undertaken at a monthly frequency to establish a baseline data for groundwater levels in each monitoring bore. Manual monitoring is suitable for identification of long term trends in groundwater levels but does not provide data on short term events such as rainfall recharge that can occur within a monthly monitoring cycle.

It is therefore recommended that for the longterm monitoring of groundwater levels, electronic water level loggers are installed in the monitoring bores and set to record groundwater level measurements at regular intervals (i.e., at least daily or even every six-hours). This will enable continuous measurement of groundwater level fluctuations to determine to what extent these are attributable to rainfall recharge, CSG pumping or from potential water level declines from depressurisation resulting from open cut mining. Monthly manual measurements should still be conducted to verify the electronic water level data.

11.3 Water quality monitoring plan Groundwater quality sampling of existing monitoring bores should continue in order to provide long-term baseline groundwater quality, and to detect any changes in groundwater quality during and post mining.

The full groundwater quality suite should include:  physio-chemical parameters – pH, electrical conductivity, total dissolved solids;  major ions – calcium, magnesium, sodium, potassium, chloride, sulphate, alkalinity (carbonate and bicarbonate); and  total and dissolved metals – arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc.

All groundwater monitoring, water level measurements and sample collection, storage and transportation should be undertaken in accordance with the procedures outlined by the Murray Darling Basin Commission (1997) and the Department of Environment and Heritage Protection (2009). Additionally, all groundwater quality and water level monitoring data will be reviewed quarterly after each monitoring event and following download of the water level data loggers by a suitably qualified person.

11.4 Groundwater triggers

The aim of trigger levels is to provide advanced warning of water level and quality trends that may be departing from historical or predicted values. Once groundwater monitoring data has been accepted, processed, and input into the relevant groundwater database, the data will be compared against the trigger limit values and thresholds for the various parameters prescribed by the EA conditions.

11.4.1 Groundwater level trigger thresholds

The existing monitoring bore network is located within the proposed mining footprint and will ultimately be mined out. These bores are therefore expected to measure drawdown that will range from a few metres and tens of metres. Drawdown compared to the predictions of groundwater drawdown for the Project will be used to identify divergence between predicted and observed measurements, and assess the likely causes of these discrepancies.

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Table 11.2 presents groundwater level change trigger thresholds for the existing monitoring bores, outside of normal seasonal fluctuations. When groundwater level monitoring results are compared to the groundwater level trigger thresholds:  if the results do not exceed the level trigger thresholds then no further action is required; or  if the results exceed the level thresholds, an exceedance investigation and response will be initiated.

Table 11.2 Groundwater level trigger thresholds

Monitoring location Level trigger threshold1

CD034C 5 m total

CD036R 32 m total

CD037C 18 m total

CD056 50 m total

CD065 6 m total

Note: 1 The level trigger threshold is equal to the groundwater level drawdown observed within each monitoring bore measured from the commencement of mining.

Groundwater level triggers for the proposed monitoring bores MB1 to MB12 will be determined after these bores are installed, and their locations and aquifer intersected confirmed.

11.4.2 Groundwater quality trigger values

Groundwater quality trigger values developed for the Project provide a threshold, above which some further consideration of the data should be given. The trigger values are not a pass or fail assessment, but act as a warning system that initiates further investigation and response.

The trigger values have been assessed by analysing the water quality datasets collected between April 2009 and November 2016. This dataset identifies the water is typically saline making it unsuitable for stock watering, and supports the 2017 bore census which identified no significant use of groundwater by landholders surrounding the Project. Review of the environmental values identifies groundwater accessed by the Project would only provide a beneficial use for industrial purposes. On this basis and in line with recommendation provided by DES, water quality trigger levels have been determined for the following parameters:  pH, EC and sulphate; and  total metals concentrations for arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc.

The ANZECC & ARMCANZ aquatic ecosystems protection toxicity triggers (ANZECC, 2000) apply to fresh and marine water environments, both of which are not representative of the saline aquifer hosted within the Walloon Coal Measures. Adopting these values as trigger levels for Cameby Downs Mine is therefore not considered appropriate, and would result in persistent and repeated exceedances for nearly all the parameters analysed. Table 11.3 summarises the Cameby Downs Mine groundwater quality data, and the extent to which the data collected to date would exceed the ANZECC & ARMCANZ (ANZECC, 2000) aquatic ecosystem triggers. For sulphate and mercury, comparison of this data has used the ANZECC & ARMCANZ (ANZECC, 2000) livestock drinking water quality guidelines.

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Table 11.3 Comparison of Cameby Downs Mine groundwater quality data and ecosystem trigger values

Summary of CDM site groundwater quality data Percent Ecosystem trigger1 Parameter Unit exceedance by

Minimum Maximum Average CDM site data pH - 5.5 8.4 6.7 6.5-8.0 7%

Electrical S/cm 720 35,300 14,586 125-2,200 100% Conductivity

Not provided NA3 Sulfate mg/L 1 1,040 199 (1,0002) (3%2)

Arsenic III4 mg/L 0.001 0.025 0.005 0.024 0%

Cadmium mg/L 0.0001 0.0016 0.0004 0.0002 39%

Chromium mg/L 0.0006 0.05 0.006 0.001 73%

Copper mg/L 0.002 0.123 0.0123 0.0014 95%

Lead mg/L 0.001 0.114 0.008 0.0034 32%

Mercury mg/L 0.002 0.002 0.002 0.0006 (0.0022) 1% (1%2)

Nickel mg/L 0.001 0.058 0.013 0.011 41%

Zinc mg/L 0.005 1.4 0.15 0.008 96%

Notes: 1: ANZECC & ARMCANZ (2000), freshwater aquatic ecosystem trigger (level of protection for 95% of species) 2: ANZECC & ARMCANZ (2000), livestock drinking water quality guideline 3: Not assessable 4: Arsenic III is the form of arsenic that predominates in groundwater (NHMRC & NRMMC, 2011)

DSITI (2017b) provides recommendation for adopting local triggers that are based on the level of protection that has been attributed to the groundwater system. For example, the document recommends using the 80th percentiles (and 20th percentile for pH) of reference bores values for slightly to moderately disturbed waters, but using a less stringent guideline for highly disturbed systems.

Review of the water quality data identifies only that for pH, EC and TDS were sampled prior to mining commencing, whilst the remaining data was collected after mining commenced in 2010. The data has been obtained from (compliance) bores located within the mining area. On this basis and considering the limited environmental value for the groundwater (refer Section 8), an alternative approach for determining appropriate triggers levels adopts the 95% percentile values for each parameter, determined from all sampling undertaken to date at Cameby Downs Mine. The proposed groundwater quality trigger values for Cameby Downs Mine are presented in Table 11.4. The exceptions are for:  sulphate which uses the default ANZECC & ARMCANZ livestock drinking water quality guideline (1,000 mg/L) as there is no aquatic ecosystem trigger value, and it is similar to the derived 95th percentile (986 mg/L) of all the available site data;  arsenic which uses the ANZECC & ARMCANZ (2000) aquatic ecosystem trigger (0.024 mg/L); and  mercury, which uses the ANZECC & ARMCANZ livestock drinking water quality guideline (0.002 mg/L) which is the same as the reported value from the site data collected to date that was greater than the laboratory’s limit of reporting, and is considered to be the most appropriate interim trigger until such time that sufficient data can be collected.

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Table 11.4 Proposed Cameby Downs Mine groundwater quality trigger values

Unit Percent Proposed Parameter exceedance by site trigger site data

pH - 5.7-7.5 6%

Electrical conductivity S/cm 27,880 6%

Sulfate mg/L 1,0001 3%

Arsenic mg/L 0.0242 1%

Cadmium mg/L 0.0009 3%

Chromium mg/L 0.016 5%

Copper mg/L 0.042 5%

Lead mg/L 0.018 4%

Mercury mg/L 0.0021 1%

Nickel mg/L 0.026 5%

Zinc mg/L 0.703 5%

Notes: 1 ANZECC & ARMCANZ (2000), livestock drinking water quality guideline 2 ANZECC & ARMCANZ (2000), freshwater aquatic ecosystem trigger (level of protection for 95% of species)

The proposed triggers are therefore based on site groundwater quality data, and are considered to be “fit for purpose” for the type of saline groundwater environment being assessed. That is, the proposed triggers are designed to provide opportunity for establishing early warning of any emerging potential impacts to the groundwater quality, whilst not necessarily resulting in repeated exceedance of each parameter with each sampling event.

11.5 Mine groundwater inflow monitoring

It is recommended that monitoring of groundwater pit inflows should be undertaken routinely, particularly to identify inflow/seepage rates and quality. The frequency of this monitoring should be undertaken in consultation with a suitably qualified person, e.g. daily to weekly for up to one month following an abrupt increase in pit inflows. The frequency should then be reviewed and where appropriate adjusted accordingly. Water samples should be collected of any pumped seepage and laboratory analysis for same suite of parameters for the groundwater monitoring bores. The groundwater pit inflow monitoring program should include:  recording of any unexpected or significantly increased groundwater inflows directly to the pits;  measurement of water pumped from the pits;  sampling of water quality pumped from the pits; and  monitoring of rainfall (to allow for correlation with pumping/pit inflow records).

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11.6 Data management and reporting

It is recommended that data management and reporting by the proponent includes an annual monitoring report which should include:  records of groundwater levels and quality in the monitoring network bores ; and  details of any review undertaken of the groundwater model since the previous annual monitoring report (NB: A review of the groundwater model should be undertaken within five years of commencement of the Cameby Downs Mine Continued Operations Project by a suitably qualified hydrogeologist).

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12 Conclusions

This report has evaluated the impact of the Project. The Project involves increasing the life of the Cameby Downs Mine from the currently approved rate of 2.8 Mtpa for 45 years to 75 years (from 2016) at an increased mining rate of 3.5 Mtpa. This requires an Environmental Authority amendment and referral to the Commonwealth under the EPBC Act. The study has used results from the previous groundwater assessments (AGE, 2006; AGE, 2010; AGE, 2013; and AGE, 2015), groundwater level data, groundwater chemistry data and the geological data available for the Project area. The conclusions of the assessment of the Project on the groundwater resources are listed below:  The primary groundwater units impacted by the Project are the Walloon Coal Measures and also the Kumbarilla Beds where these are saturated.  Groundwater quality is brackish to highly saline, making it unsuitable as a potable source, and also for livestock watering and other agricultural uses such as irrigation.  There are no landholder water supply bores located within the predicted drawdown extents attributable to the proposed mine plan for the Project.  The bore census undertaken for this assessment identified no use of groundwater from either the Walloon Coal Measures or Kumbarilla Beds surrounding the Project. This is due to the aquifers being either unsaturated or partially unsaturated in the vicinity of the Cameby Downs Mine (as is the case with the Springbok Formation within the Kumbarilla Beds), or saline as is the case with the Walloon Coal Measures.  Cumulative impacts in the region were assessed to be largely due to impacts from CSG activities, which partially overlap with the Project area. The Walloon Coal Measures IAA and LAA and the Springbok Sandstone LAA encompass all or some of the Project area (OGIA, 2016). As such, this assessment indicates the Project will only add a small to moderate ‘water take’ that is predicted to be comparatively low compared to the already approved CSG operations.  The assessment identifies that there are no watercourses with associated productive alluvial aquifers within the Project area and there will be no impact from mining on localised shallow alluvial or perched aquifers that may be associated with minor surface drainage features within the Project area.  The Project is not predicted to impact any aquatic or terrestrial GDEs since GDEs are assessed as being unlikely to occur within and surrounding the Project area.  This assessment predicts the final pit voids will act as long-term groundwater sinks post mining, with pit void water levels expected to recover to a quasi-equilibrium level that is approximately 20 m to 25 m below the pre-mining groundwater level. This will result in the long-term water quality within the final voids being affected by evaporative concentration and becoming more saline. However, flow of this water into the groundwater systems will be prevented as a consequence of the lower water level within the voids.  Although the overburden consists primarily of non-acid forming material, coal rejects and overburden material will be contained within in-pit storage emplacements, and final voids will act as a sink to groundwater flow. As such, any resultant impact to void water quality will be contained at the site.  Groundwater level and water quality triggers have been determined from water quality data collected between April 2009 and November 2016. Groundwater quality triggers have been established for the suite of parameters currently included for the groundwater monitoring.  Comparison of the potential impacts against the DotE (2013) guidelines concludes that the Project is not likely to have a significant impact on groundwater resources.

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13 References

Australasian Groundwater and Environmental Consultants Pty Ltd (2006), ‘Report on Groundwater Impact Assessment - Cameby Downs Coal Project’, prepared for Syntech Resources Pty Ltd, Project No. G1227/A, October 2006 (unpublished).

Australasian Groundwater and Environmental Consultants Pty Ltd (2010), ‘Groundwater impact assessment - Cameby Downs Expansion Project’, prepared for Syntech Resources Pty Ltd, Project No. G1476, April 2010 (unpublished).

Australasian Groundwater and Environmental Consultants Pty Ltd (2013), ‘Groundwater impact assessment - Cameby Downs Expansion Project’, prepared for Syntech Resources Pty Ltd, Project No. G1597, January 2013 (unpublished).

Australasian Groundwater and Environmental Consultants Pty Ltd (2015), ‘Groundwater Monitoring Report - Cameby Downs Mine’, prepared for Syntech Resources Pty Ltd, Project No. G1728, June 2015 (unpublished).

Australian and New Zealand Environment and Conservation Council (2000), ‘Australia and New Zealand Guidelines for Fresh and Marine Water Quality’.

Bureau of Meteorology (2017), ‘Groundwater Dependent Ecosystem Atlas’, Australian Government, accessed 3rd October 2016.

Barnett, B., Townley, L.R., Post, V., Evans, R.E., Hunt, R.J., Peeters, L., Richardson, S., Werner, A.D., Knapton, A., & Boronkay, A., (2012), ‘Australian groundwater modelling guidelines’, Waterlines report, National Water Commission, Canberra

Burns, L (2016), ‘RE: G1831: Cumulative Impacts, GDEs, and Mining Inflows’ [email: 13/10/2016].

Commonwealth of Australia (2018), ‘Information guidelines for proponents preparing coal seam gas and large coal mining development proposals’. Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development, May, 2018.

Condamine Alliance, (2017), “Draft Groundwater Environmental Values for the Condamine Catchment, Queensland”, Republished March 2017 as part of the statutory review of the Environmental Protection (Water) Policy 2009.

Department of Environment and Science (2018), ‘Monitoring and Sampling Manual: Environmental Protection (Water) Policy’, February 2018.

Department of Environment and Heritage Protection, (2012), ‘Recording, interpretation & analysis of monitoring results – ERA 60 – Waste Disposal’, Environmental Protection Act 1994, Version 1, August 2012.

Department of Natural Resources, Mines and Energy (2017), ‘Groundwater Database - Queensland’, https://data.qld.gov.au/dataset/groundwater-database-queensland.

Department of Science, Information Technology and Innovation, (2017a), ‘Groundwater dependent ecosystems and potential aquifer mapping – Queensland’, Queensland Government, licensed under Creative Commons Attribution 4.0 sourced on 16 November 2017.

Department of Science, Information Technology and Innovation, (2017b), ‘Using monitoring data to assess groundwater quality and potential environmental impacts’, Queensland Government, licensed under Creative Commons Attribution 3.0, March 2017.

Department of the Environment, (2103), ‘Significant impact guidelines 1.3: Coal seam gas and large coal mining developments – impacts on water resources’, Commonwealth of Australia, December 2013.

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | 88

DPM Envirosciences, (2017), ‘Cameby Downs Continued Operations Project Aquatic Ecology Assessment’, report prepared for Syntech Resources Pty Ltd.

Ecowise Environmental (2010), ‘Cameby Downs Mine Expansion Project – Stygofauna’, prepared for Syntech Resources Pty Ltd, February 2010.

Ecosure, (2017), ‘Cameby Downs Continued Operations Project Flora Assessment’, report prepared for Syntech Resources Pty Ltd.

FAO (2013), Food and Agricultural Organisation of the United Nations: http://www.fao.org/docrep/t0667e/t0667e05.htm.

GHD (2012), ‘Report for QWC17-10 Stage 2, Surat Cumulative Management Area Groundwater Model Report’, prepared for Queensland Water Commission, May 2012.

Murray Darling Basin Commission (1997), ‘Murray Darling Basin Groundwater Quality Sampling Guidelines’, Technical Report No. 3, MDBC Groundwater Working Group, Commonwealth of Australia.

NHMRC, NRMMC (2011), ‘Australian Drinking Water Guidelines Paper 6 National Water Quality Management Strategy’. National Health and Medical Research Council, National Resource Management Ministerial Council, Commonwealth of Australia, Canberra.

OGIA (2016), ‘Underground Water Impact Report for the Surat Cumulative Management Area’, compiled by the Office of Groundwater Impact Assessment, Department of Natural Resources, September 2016.

Smerdon, B.D., Ransley, T.R., Radke, B.M., and Kellett, J.R., (2012), ‘Water resource assessment for the Great Artesian Basin’, A report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment, CSIRO Water for a Healthy Country Flagship, Australia.

SRK Consulting (2012), ‘Cameby Downs Expansion: Geochemical characterisation’, prepared for Syntech Resources Pty Ltd, June 2012.

Sheskin, D, J., (2011), ‘Handbook of Parametric and Nonparametric Statistical Procedures’, published by Chapman & Hall / CRC, Taylor and Francis Group, Boca Raton.

Syntech Resources (2016), ‘Cameby Downs Mine Continued Operations Report. Section 226 Consideration Report ’, project no. SYN-16-02, November 2016.

QGC (2012), ‘Surat Basin Stratigraphic Framework’, Appendix D of the Stage 2 CSG water monitoring management plan, April 2012.

Yancoal, (2016), ‘Cameby Downs Mine Continued Operations Project Section 226 Consideration Report,’ Project No. YAN-12-01, Document No. 100756786, prepared by Yancoal Australia Ltd, August 2016.

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Appendix A IESC Guidelines

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | Appendix A A1 Independent Expert Scientific Committee guidelines

The Independent Expert Scientific Committee (IESC) on Coal Seam Gas and Large Coal Mining Development has information guidelines for advice on coal seam gas and large coal mining development proposals (CoA, 20181). The following section specifies where the IESC information requirements for individual proposals have been addressed within this report.

A1.1 Description of the proposal

Addressed in Project Information section

Provide a regional overview of the proposed project area including a description of the geological basin; coal resource; surface water catchments; groundwater systems; Sections 1, 3, water-dependent assets; and past, present and reasonably foreseeable coal mining 4, 5, 6 & 8 and CSG developments.

Describe the statutory context, including information on the proposal’s status within the regulatory assessment process and any applicable water management policies or Sections 2 & 8 regulations.

Describe the proposal’s location, purpose, scale, duration, disturbance area, and the means by which it is likely to have a significant impact on water resources and Sections 1 & 8 water-dependent assets.

Describe how impacted water resources are currently being regulated under state or Commonwealth law, including whether there are any applicable standard Sections 2 & 10 conditions.

A1.2 Risk Assessment

Addressed in Project Information section

Identify and assess all potential environmental risks to water resources and water- related assets, and their possible impacts. In selecting a risk assessment approach Sections 7, 8, 9, 10, consideration should be given to the complexity of the project, and the probability & Appendix E and potential consequences of risks.

Assess risks following the implementation of any proposed mitigation and Sections 9, 10, & management options to determine if these will reduce risks to an acceptable level Appendix E based on the identified environmental objectives.

Incorporate causal mechanisms and pathways identified in the risk assessment in Section 9 & conceptual and numerical modelling. Use the results of these models to update the Appendix E risk assessment.

1 Commonwealth of Australia (CoA) 2018), ‘Information guidelines for proponents preparing coal seam gas and large coal mining development proposals’. Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development, May, 2018.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Middlemount Western Extension Project (G1840D) | Appendix A | 1 Addressed in Project Information section

The risk assessment should include an assessment of:  all potential cumulative impacts which could affect water resources and water-related assets; and, Sections 9 & 10  mitigation and management options which the proponent could implement to reduce these impacts.

A1.3 Groundwater – Context and conceptualisation

Addressed in Project Information section

Describe and map geology at an appropriate level of horizontal and vertical resolution including:  definition of the geological sequence(s) in the area, with names and descriptions of the formations and accompanying surface geology, cross- Section 5 & sections and any relevant field data; and Section 5.3  geological maps appropriately annotated with symbols that denote fault type, throw and the parts of sequences the faults intersect or displace.

Define and describe or characterise significant geological structures (e.g. faults, folds, intrusives) and associated fracturing in the area and their influence on groundwater – particularly groundwater flow, discharge or recharge.  Site-specific studies (e.g. geophysical, coring / wireline logging etc.) should give consideration to characterising and detailing the local stress regime Section 6 and fault structure (e.g. damage zone size, open/closed along fault plane, presence of clay/shale smear, fault jogs or splays).  Discussion on how this fits into the fault’s potential influence on regional- scale groundwater conditions should also be included.

Provide site-specific values for hydraulic parameters (e.g. vertical and horizontal hydraulic conductivity and specific yield or specific storage characteristics including the data from which these parameters were derived) for each relevant Section 6 hydrogeological unit. In situ observations of these parameters should be sufficient to characterise the heterogeneity of these properties for modelling.

Provide time series level and water quality data representative of seasonal and Section 6 & climatic cycles. Appendix E

Provide data to demonstrate the varying depths to the hydrogeological units and associated standing water levels or potentiometric heads, including direction of Section 6 groundwater flow, contour maps, and hydrographs. All boreholes used to provide this data should have been surveyed.

Provide hydrochemical (e.g. acidity/alkalinity, electrical conductivity, metals, and major ions) and environmental tracer (e.g. stable isotopes of water, tritium, helium, strontium isotopes, etc.) characterisation to identify sources of water, recharge Section 6 rates, transit times in aquifers, connectivity between geological units and groundwater discharge locations.

Describe the likely recharge, discharge and flow pathways for all hydrogeological Section 6.8 units likely to be impacted by the proposed development.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 2 Addressed in Project Information section

Assess the frequency (and time lags if any), location, volume and direction of interactions between water resources, including surface water/groundwater Section 6 connectivity, inter-aquifer connectivity and connectivity with sea water.

A1.4 Groundwater – Numerical modelling

Addressed in Project Information section

Provide a detailed description of all analytical and/or numerical models used, and Section 9 & any methods and evidence (e.g. expert opinion, analogue sites) employed in addition Appendix E to modelling.

Undertaken groundwater modelling in accordance with the Australian Groundwater Section 9.3 & Modelling Guidelines (Barnett et al. 2012), including independent peer review. Appendix E1.1

Calibrate models with adequate monitoring data, ideally with calibration targets Section 8.2.3 & related to model prediction (e.g. use baseflow calibration targets where predicting Appendix E changes to baseflow).

Describe each hydrogeological unit as incorporated in the groundwater model, including the thickness, storage and hydraulic characteristics, and linkages between Appendix E2.3 units, if any.

Describe the existing recharge/discharge pathways of the units and the changes that are predicted to occur upon commencement, throughout, and after completion of Appendix E 2.4 the proposed project.

Describe the various stages of the proposed project (construction, operation and rehabilitation) and their incorporation into the groundwater model. Provide Sections 9.3, 2.3 & predictions of water level and/or pressure declines and recovery in each Appendix E hydrogeological unit for the life of the project and beyond, including surface contour maps for all hydrogeological units.

Identify the volumes of water predicted to be taken annually with an indication of Section 9.4 the proportion supplied from each hydrogeological unit.

Undertake model verification with past and/or existing site monitoring data. Appendix E3

Provide an explanation of the model conceptualisation of the hydrogeological Section 7 & system or systems, including multiple conceptual models if appropriate. Key Appendix E2.1 assumptions and model limitations and any consequences should also be described.

Consider a variety of boundary conditions across the model domain, including constant head or general head boundaries, river cells and drains, to enable a Appendix 2.4.6 comparison of groundwater model outputs to seasonal field observations.

Undertake sensitivity analysis and uncertainty analysis of boundary conditions and hydraulic and storage parameters, and justify the conditions applied in the final Appendix E4 groundwater model (see Middlemis and Peeters [in press]).

Provide an assessment of the quality of, and risks and uncertainty inherent in, the data used to establish baseline conditions and in modelling, particularly with respect Section 6 to predicted potential impact scenarios.

Undertake an uncertainty analysis of model construction, data, conceptualisation Section 9.4.2 and predictions (see Middlemis and Peeters [in press]).

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 3 Addressed in Project Information section

Provide a program for review and update of models as more data and information Section 11 become available, including reporting requirements.

Provide information on the magnitude and time for maximum drawdown and post- Section 9.5 development drawdown equilibrium to be reached.

A1.5 Groundwater – Impacts on water resources and water dependent assets

Addressed in Project Information section

Provide an assessment of the potential impacts of the proposal, including how impacts are predicted to change over time and any residual long-term impacts. Consider and describe:  any hydrogeological units that will be directly or indirectly dewatered or depressurised, including the extent of impact on hydrological interactions Section 9.4.2 between water resources, surface water/groundwater connectivity, inter- aquifer connectivity and connectivity with sea water;  the effects of dewatering and depressurisation (including lateral effects) on water resources, water-dependent assets, groundwater, flow direction and Section 8.3 surface topography, including resultant impacts on the groundwater balance;  the potential impacts on hydraulic and storage properties of N/A hydrogeological units, including changes in storage, potential for physical transmission of water within and between units, and estimates of likelihood of leakage of contaminants through hydrogeological units; and  the possible fracturing of and other damage to confining layers. N/A  For each relevant hydrogeological unit, the proportional increase in groundwater use and impacts as a consequence of the proposed project, N/A including an assessment of any consequential increase in demand for groundwater from towns or other industries resulting from associated population or economic growth due to the proposal

Describe the water resources and water-dependent assets that will be directly impacted by mining or CSG operations, including hydrogeological units that will be Section 9.4.3 exposed/partially removed by open cut mining and/or underground mining.

For each potentially impacted water resource, provide a clear description of the impact to the resource, the resultant impact to any water-dependent assets Section 9.4 dependent on the resource, and the consequence or significance of the impact.

Describe existing water quality guidelines, environmental flow objectives and other requirements (e.g. water planning rules) for the groundwater basin(s) within which Sections 2 & 8 the development proposal is based.

Provide an assessment of the cumulative impact of the proposal on groundwater when all developments (past, present and/or reasonably foreseeable) are Section 9.5 considered in combination.

Describe proposed mitigation and management actions for each significant impact identified, including any proposed mitigation or offset measures for long-term Section 9.5.2 impacts post mining.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 4 Addressed in Project Information section

Section 11 and refer to Receiving Provide a description and assessment of the adequacy of proposed measures to Environment prevent/minimise impacts on water resources and water-dependent assets. Monitoring Program

A1.6 Groundwater – Data and monitoring

Addressed in Project Information section

Provide sufficient data on physical aquifer parameters and hydrogeochemistry to establish pre-development conditions, including fluctuations in groundwater levels Section 11 at time intervals relevant to aquifer processes.

Develop and describe a robust groundwater monitoring program using dedicated groundwater monitoring wells – including nested arrays where there may be connectivity between hydrogeological units – and targeting specific aquifers, Section 11 providing an understanding of the groundwater regime, recharge and discharge processes and identifying changes over time.

Develop and describe proposed targeted field programs to address key areas of uncertainty, such as the hydraulic connectivity between geological formations, the sources of groundwater sustaining GDEs, the hydraulic properties of significant Section 11 faults, fracture networks and aquitards in the impacted system, etc., where appropriate.

Provide long-term groundwater monitoring data, including a comprehensive assessment of all relevant chemical parameters to inform changes in groundwater Section 11 quality and detect potential contamination events.

Ensure water quality monitoring complies with relevant National Water Quality Management Strategy (NWQMS) guidelines (ANZECC/ARMCANZ 2000) and relevant Section 11 legislated state protocols (e.g. QLD Government 2013).

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 5 A1.7 Water dependent assets – Context and conceptualisation

Addressed in Project Information section

Identify water-dependent assets, including:  water-dependent fauna and flora and provide surveys of habitat, flora and fauna (including stygofauna) (see Doody et al. [in press]); and Sections 6.10 & 7  public health, recreation, amenity, Indigenous, tourism or agricultural values for each water resource.

Identify GDEs in accordance with the method outlined by Eamus et al. (2006). Information from the GDE Toolbox (Richardson et al. 2011) and GDE Atlas (CoA Section 6.10 2017a) may assist in identification of GDEs (see Doody et al. [in press]).

Describe the conceptualisation and rationale for likely water-dependence, impact pathways, tolerance and resilience of water-dependent assets. Examples of Section 6. 10 ecological conceptual models can be found in Commonwealth of Australia (2015).

Estimate the ecological water requirements of identified GDEs and other water- Section 6. 10 dependent assets (see Doody et al. [in press]).

Identify the hydrogeological units on which any identified GDEs are dependent (see Section 6. 10 Doody et al. [in press]).

Provide an outline of the water-dependent assets and associated environmental Section 9.4.6 objectives and the modelling approach to assess impacts to the assets.

Describe the process employed to determine water quality and quantity triggers and impact thresholds for water-dependent assets (e.g. threshold at which a significant Section 9.4.6 impact on an asset may occur).triggers and impact thresholds for water-dependent assets (e.g. threshold at which a significant impact on an asset may occur).

A1.8 Water dependent assets – Impacts, risk assessment and management of risks

Addressed in Project Information section

Provide an assessment of direct and indirect impacts on water-dependent assets, including ecological assets such as flora and fauna dependent on surface water and Section 9.4.6 groundwater, springs and other GDEs (see Doody et al. [in press]).

Describe the potential range of drawdown at each affected bore, and clearly Section 9.4.5 articulate of the scale of impacts to other water users.

Indicate the vulnerability to contamination (e.g. from salt production and salinity) and the likely impacts of contamination on the identified water-dependent assets Sections 9.6 and ecological processes.

Identify and consider landscape modifications (e.g. voids, on-site earthworks, and roadway and pipeline networks) and their potential effects on surface water flow, Section 9.5 erosion and habitat fragmentation of water-dependent species and communities.

Provide estimates of the volume, beneficial uses and impact of operational discharges of water (particularly saline water), including potential emergency Refer to Surface discharges due to unusual events, on water-dependent assets and ecological Water Assessment processes.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 6 Addressed in Project Information section

Assess the overall level of risk to water-dependent assets through combining Section 9.4.6 probability of occurrence with severity of impact.

Identify the proposed acceptable level of impact for each water-dependent asset based on leading-practice science and site-specific data, and ideally developed in Section 8 conjunction with stakeholders.

Propose mitigation actions for each identified impact, including a description of the Section 10.5 adequacy of the proposed measures and how these will be assessed.

A1.9 Water dependent assets – Data and monitoring

Addressed in Project Information section

Identify an appropriate sampling frequency and spatial coverage of monitoring sites to establish pre-development (baseline) conditions, and test potential responses to Section 11 impacts of the proposal (see Doody et al. [in press]).

Consider concurrent baseline monitoring from unimpacted control and reference sites to distinguish impacts from background variation in the region (e.g. BACI Section 11 design, see Doody et al. [in press]).

Develop and describe a monitoring program that identifies impacts, evaluates the effectiveness of impact prevention or mitigation strategies, measures trends in Section 11 ecological responses and detects whether ecological responses are within identified thresholds of acceptable change (see Doody et al. [in press]).

Describe the proposed process for regular reporting, review and revisions to the Section 11 monitoring program.

Refer to Receiving Ensure ecological monitoring complies with relevant state or national monitoring Environment guidelines (e.g. the DSITI guideline for sampling stygofauna [QLD Government Monitoring 2015]). Program

A1.10 Water and salt balance and water management strategy

Addressed in Project Information section

Provide a quantitative site water balance model describing the total water supply Refer to Surface and demand under a range of rainfall conditions and allocation of water for mining Water Assessment activities (e.g. dust suppression, coal washing etc.), including all sources and uses.

Describe the water requirements and on-site water management infrastructure, Refer to Surface including modelling to demonstrate adequacy under a range of potential climatic Water Assessment conditions.

Provide estimates of the quality and quantity of operational discharges under dry, Refer to Surface median and wet conditions, potential emergency discharges due to unusual events Water Assessment and the likely impacts on water-dependent assets.

Provide salt balance modelling that includes stores and the movement of salt Refer to Surface between stores, and takes into account seasonal and long-term variation. Water Assessment

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 7 A1.11 Cumulative Impacts – Context and conceptualisation

Addressed in Project Information section

Provide cumulative impact analysis with sufficient geographic and temporal Section 9.4.3 boundaries to include all potentially significant water-related impacts.

Consider all past, present and reasonably foreseeable actions, including development proposals, programs and policies that are likely to impact on the water resources of concern in the cumulative impact analysis. Where a proposed project is Section 9.4.3 located within the area of a bioregional assessment consider the results of the bioregional assessment.

A1.12 Cumulative Impacts – Impacts

Addressed in Project Information section

Provide an assessment of the condition of affected water resources which includes:  identification of all water resources likely to be cumulatively impacted by the proposed development;  a description of the current condition and quality of water resources and information on condition trends;  identification of ecological characteristics, processes, conditions, trends and Section 9.4.3 values of water resources;  adequate water and salt balances; and  identification of potential thresholds for each water resource and its likely response to change and capacity to withstand adverse impacts (e.g. altered water quality, drawdown).

Assess the cumulative impacts to water resources considering:  the full extent of potential impacts from the proposed project, (including whether there are alternative options for infrastructure and mine configurations which could reduce impacts), and encompassing all linkages, including both direct and indirect links, operating upstream, downstream, vertically and laterally;  all stages of the development, including exploration, operations and post Section 9.4.3 and closure / decommissioning; Section 9.5  appropriately robust, repeatable and transparent methods;  the likely spatial magnitude and timeframe over which impacts will occur, and significance of cumulative impacts; and  opportunities to work with other water users to avoid, minimise or mitigate potential cumulative impacts.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 8 A1.13 Cumulative Impacts – Mitigation, monitoring and management

Addressed in Project Information section

Identify modifications or alternatives to avoid, minimise or mitigate potential Refer to Surface cumulative impacts. Evidence of the likely success of these measures (e.g. case Water Assessment studies) should be provided. Identify measures to detect and monitor cumulative impacts, pre and post Refer to Surface development, and assess the success of mitigation strategies. Water Assessment Refer to Surface Identify cumulative impact environmental objectives. Water Assessment Refer to Surface Describe appropriate reporting mechanisms. Water Assessment Refer to Surface Propose adaptive management measures and management responses. Water Assessment

A1.14 Final landform and voids – coal mines

Addressed in Project Information section

Identify and consider landscape modifications (e.g. voids, on-site earthworks, and roadway and pipeline networks) and their potential effects on surface water flow, Section 9.5 erosion, sedimentation and habitat fragmentation of water-dependent species and communities.

Assess the adequacy of modelling, including surface water and groundwater Section 9.5 quantity and quality, lake behaviour, timeframes and calibration.

Provide an evaluation of stability of void slopes where failure during extreme events or over the long term (for example due to aquifer recovery causing geological heave Section 9.6 and landform failure) may have implications for water quality.

Evaluate mitigating inflows of saline groundwater by planning for partial backfilling Section 9.6 of final voids.

Provide an assessment of the long-term impacts to water resources and water- dependent assets posed by various options for the final landform design, including complete or partial backfilling of mining voids. Assessment of the final landform for which approval is being sought should consider:  groundwater behaviour – sink or lateral flow from void;  water level recovery – rate, depth, and stabilisation point (e.g. timeframe and level in relation to existing groundwater level, surface elevation); Sections 9.5 & 9.6  seepage – geochemistry and potential impacts;  long-term water quality, including salinity, pH, metals and toxicity; and  measures to prevent migration of void water off-site. For other final landform options considered sufficient detail of potential impacts should be provided to clearly justify the proposed option.

Assess the probability of overtopping of final voids with variable climate extremes, Section 9.6 and management mitigations.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 9 A1.15 Acid-forming materials and other contaminants of concern

Addressed in Project Information section

Identify the presence and potential exposure of acid-sulphate soils (including Section 6.7.1 oxidation from groundwater drawdown).

Identify the presence and volume of potentially acid-forming waste rock, fine- grained amorphous sulphide minerals and coal reject/tailings material and Section 9.6 exposure pathways.

Identify other sources of contaminants, such as high metal concentrations in Sections 6.7 groundwater, leachate generation potential and seepage paths.

Describe handling and storage plans for acid-forming material (co-disposal, tailings Section 9.6 dam, and encapsulation).

Assess the potential impact to water-dependent assets, taking into account dilution factors, and including solute transport modelling where relevant, representative and Section 9.4.6 statistically valid sampling, and appropriate analytical techniques.

Describe proposed measures to prevent/minimise impacts on water resources, Section 9.6 water users and water-dependent ecosystems and species.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs Continued Operations Project (G1831) | Appendix A | 10

Appendix B Cameby Downs Mine – Water Quality Data, April 2009 to January 2016

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | Appendix B G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD018 CD018 CD018 CD018 CD018 CD018 CD018 CD018 CD018 Sample Location Drinking Stock Water Date Sampled Water 21/4/09 26/11/09 25/2/10 9/7/10 27/7/11 28/10/11 4/1/12 25/7/12 28/11/12 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 7.11 7.43 7 6.83 7.12 Electrical conductivity µS/cm 1 - - 33200 35300 6690 6730 26842 Total Dissolved Solids mg/L 1 5000* 600b 21600 25200 4700 4563 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 234 185 140 154 112 Total Alkalinity as CaCO3 mg/L 1 - - 234 185 140 154 112 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 2 <1 <1 <1 <5 Chloride mg/L 1 - 250b 7890 5680 3810 4470 2660 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 199 141 93 112 70 Magnesium mg/L 1 - - 365 255 162 203 117 Sodium mg/L 1 - 180b 3950 2820 1930 2280 1370 Potassium mg/L 1 - - 24 14 11 15 10 Total Anions meq/L 0.01 - - 227 164 110 129 77.3 Total Cations meq/L 0.01 - - 212 151 102 122 73 Ionic Balance % 0.01 - - 3.4 4.1 3.81 2.93 2.88 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.001 <0.001 0.007 <0.001 Cadmium mg/L 0.001 0.01 - 0.0002 <0.0001 <0.0001 <0.0001 <0.0001 Chromium mg/L 0.001 1 - 0.005 0.002 0.005 0.008 0.002 Copper mg/L 0.05 1* - 0.029 0.004 0.007 0.008 0.003 Lead mg/L 0.0001 0.1 <0.001 <0.001 <0.001 <0.001 <0.001 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.03 0.005 0.017 0.018 0.012 Zinc mg/L 0.001 20 - 0.029 0.015 0.034 0.035 0.026 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD018 CD018 CD018 CD018 CD018 CD018 CD018 CD018 Sample Location Drinking Stock Water Date Sampled Water 12/2/13 1/5/13 27/11/13 23/4/14 9/7/14 12/11/14 13/1/15 21/5/15 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.54 6.05 6.27 6.54 6.65 6.6 8.4 Electrical conductivity µS/cm 1 - - 7110 6120 8140 8150 8020 10200 Total Dissolved Solids mg/L 1 5000* 600b 5111 5210 7441 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 125 119 121 139 128 125 349 Total Alkalinity as CaCO3 mg/L 1 - - 125 119 121 139 128 125 349 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 1 <1 1 <1 4 <1 <25 Chloride mg/L 1 - 250b 2130 2500 2460 2640 2760 2770 14500 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 71 71 75 67 79 78 358 Magnesium mg/L 1 - - 115 112 112 105 118 119 612 Sodium mg/L 1 - 180b 1270 1320 1280 1460 1410 1480 7350 Potassium mg/L 1 - - 9 10 9 11 10 10 36 Total Anions meq/L 0.01 - - 62.6 72.9 71.8 77.2 80.5 80.6 416 Total Cations meq/L 0.01 - - 68.5 70.4 69.3 75.8 75.2 78.3 389 Ionic Balance % 0.01 - - 4.47 1.73 1.8 0.98 3.39 1.47 3.38 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.005 Cadmium mg/L 0.001 0.01 - <0.0001 <0.0001 0.0002 <0.0001 0.0001 <0.0001 <0.0001 <0.0005 Chromium mg/L 0.001 1 - 0.002 0.002 0.003 0.003 0.016 0.004 0.004 <0.005 Copper mg/L 0.05 1* - 0.004 0.002 0.005 0.004 0.1 0.005 0.004 <0.005 Lead mg/L 0.0001 0.1 <0.001 <0.001 <0.001 0.004 0.003 0.001 0.001 0.01 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.012 0.011 0.015 0.01 0.02 0.015 0.015 <0.005 Zinc mg/L 0.001 20 - 0.043 0.015 0.057 0.034 0.092 0.038 0.028 0.037 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD034C CD034C CD034C CD034C CD034C CD034C CD034C CD034C CD034C Sample Location Drinking Stock Water Date Sampled Water 21/4/09 9/7/10 12/2/13 2/5/13 8/6/13 27/11/13 23/4/14 9/7/14 12/11/14 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 7.03 5.75 5.67 6.23 5.62 5.46 5.67 5.8 Electrical conductivity µS/cm 1 - - 11500 16829 18160 16989.99 13790 16980 13650 Total Dissolved Solids mg/L 1 5000* 600b 7480 11284 8899 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 71 71 132 55 75 Total Alkalinity as CaCO3 mg/L 1 - - 71 71 132 55 75 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 990 980 969 1010 726 Chloride mg/L 1 - 250b 5380 5700 5990 5990 5640 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 805 806 968 846 758 Magnesium mg/L 1 - - 739 714 829 726 660 Sodium mg/L 1 - 180b 1630 1670 1780 1870 1590 Potassium mg/L 1 - - 65 65 71 54 51 Total Anions meq/L 0.01 - - 174 183 192 191 176 Total Cations meq/L 0.01 - - 174 173 196 185 163 Ionic Balance % 0.01 - - 0.06 2.61 1.04 1.69 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b 0.018 0.025 0.002 0.003 0.005 0.003 Cadmium mg/L 0.001 0.01 - <0.0005 0.0002 <0.0001 0.0001 <0.0001 0.0001 Chromium mg/L 0.001 1 - 0.006 0.002 0.003 0.003 0.008 0.002 Copper mg/L 0.05 1* - 0.012 0.007 0.007 0.006 0.01 0.006 Lead mg/L 0.0001 0.1 <0.005 0.004 0.002 0.006 0.008 0.001 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.009 0.007 0.004 0.007 0.015 0.007 Zinc mg/L 0.001 20 - 0.076 0.055 0.021 0.029 0.061 0.017 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD034C CD034C CD034C CD034C CD034C CD034C Sample Location Drinking Stock Water Date Sampled Water 13/1/15 21/5/15 10/9/15 14/1/16 16/5/16 30/11/16 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.2 6.53 5.83 6.37 6.1 Electrical conductivity µS/cm 1 - - 15050 15920 16201.9 15200 15700 Total Dissolved Solids mg/L 1 5000* 600b 9001 10488 10000 9880 10200 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 82 70 93 97 98 Total Alkalinity as CaCO3 mg/L 1 - - 82 70 93 97 98 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 835 1040 828 933 896 Chloride mg/L 1 - 250b 5360 5940 5720 5530 5160 Fluoride mg/L 0.1 <0.1 <0.1 Calcium mg/L 1 1000 - 770 821 774 819 812 Magnesium mg/L 1 - - 679 689 588 677 696 Sodium mg/L 1 - 180b 1690 1700 1410 1670 1750 Potassium mg/L 1 - - 52 59 39 50 55 Total Anions meq/L 0.01 - - 170 191 180 177 166 Total Cations meq/L 0.01 - - 169 173 149 170 185 Ionic Balance % 0.01 - - 0.3 4.79 9.42 1.96 2.86 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 0.003 <0.001 <0.001 0.002 Cadmium mg/L 0.001 0.01 - <0.0001 0.0001 <0.0001 0.0002 0.0002 Chromium mg/L 0.001 1 - <0.001 <0.001 0.005 0.05 0.002 Copper mg/L 0.05 1* - 0.002 0.004 0.006 0.007 0.123 Lead mg/L 0.0001 0.1 0.001 0.002 0.005 <0.001 <0.001 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.007 0.01 0.008 0.008 0.009 Zinc mg/L 0.001 20 - 0.018 0.039 0.158 0.041 0.138 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R Sample Location Drinking Stock Water Date Sampled Water 21/4/09 12/11/09 25/2/10 8/7/10 28/7/10 28/10/11 4/1/12 3/4/12 2/8/12 28/11/12 12/2/13 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.29 6.94 7.13 7.95 7.02 7.05 Electrical conductivity µS/cm 1 - - 7320 9960 11900 8946 1842 Total Dissolved Solids mg/L 1 5000* 600b 4760 9960 10100 7274 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 280 137 128 418 128 147 82 Total Alkalinity as CaCO3 mg/L 1 - - 280 137 128 418 128 147 82 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b <1 <1 <1 21 <1 <1 1 Chloride mg/L 1 - 250b 3530 1680 1650 4490 1220 1200 591 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 232 118 106 583 94 92 46 Magnesium mg/L 1 - - 138 70 63 376 56 56 27 Sodium mg/L 1 - 180b 1680 915 822 1580 711 678 341 Potassium mg/L 1 - - 20 9 8 25 8 9 4 Total Anions meq/L 0.01 - - 105 50.1 49.1 135 37 36.8 18.3 Total Cations meq/L 0.01 - - 96.5 51.7 46.4 129 40.4 38.9 19.4 Ionic Balance % 0.01 - - 4.29 1.52 2.8 2.27 4.46 2.81 2.96 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b 0.004 0.001 <0.001 <0.001 0.001 <0.001 <0.001 Cadmium mg/L 0.001 0.01 - 0.0002 0.0002 0.0003 <0.0001 <0.0001 0.0009 0.001 Chromium mg/L 0.001 1 - 0.007 <0.001 0.001 0.012 0.012 <0.001 0.006 Copper mg/L 0.05 1* - 0.023 0.003 0.006 0.014 0.004 0.005 0.017 Lead mg/L 0.0001 0.1 0.008 <0.001 <0.001 <0.001 <0.001 <0.001 0.007 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.005 0.012 0.026 0.058 0.011 0.02 0.024 Zinc mg/L 0.001 20 - 0.121 0.399 0.968 0.03 0.344 0.655 0.881 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R CD036R Sample Location Drinking Stock Water Date Sampled Water 1/5/13 27/11/13 13/1/14 23/4/14 9/7/14 12/11/14 21/5/15 10/9/15 14/1/16 16/5/16 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 7.01 6.77 6.86 7.3 6.79 7.35 7.59 Electrical conductivity µS/cm 1 - - 3620 7830 3470 4000 8190 12307.4 9250 Total Dissolved Solids mg/L 1 5000* 600b 5084 3900 5330 8000 6010 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 233 166 586 261 492 311 432 395 Total Alkalinity as CaCO3 mg/L 1 - - 233 166 586 261 492 311 432 395 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b <1 2 9 18 21 8 <1 4 Chloride mg/L 1 - 250b 1310 1110 1910 1510 1940 1130 3430 3100 Fluoride mg/L 0.1 <0.1 Calcium mg/L 1 1000 - 94 85 162 108 129 81 251 233 Magnesium mg/L 1 - - 58 53 96 75 84 54 119 125 Sodium mg/L 1 - 180b 725 651 1260 938 1100 690 1480 1650 Potassium mg/L 1 - - 9 7 38 12 14 10 14 17 Total Anions meq/L 0.01 - - 41.6 34.7 65.8 48.2 65 38.2 105 95.4 Total Cations meq/L 0.01 - - 41.2 37.1 71.8 52.7 61.6 38.8 87 94.1 Ionic Balance % 0.01 - - 0.47 3.38 4.34 4.44 2.73 0.63 9.53 0.70 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.001 <0.001 0.003 0.002 <0.001 <0.001 0.002 0.002 Cadmium mg/L 0.001 0.01 - 0.0007 0.0006 <0.0001 0.0004 0.0003 0.0002 0.0002 <0.0001 <0.0001 Chromium mg/L 0.001 1 - 0.009 0.004 <0.001 0.009 0.003 0.001 <0.001 0.004 0.004 Copper mg/L 0.05 1* - 0.021 0.011 0.003 0.016 0.01 0.007 0.002 0.006 0.011 Lead mg/L 0.0001 0.1 0.018 0.004 0.002 0.024 0.008 0.002 <0.001 0.004 0.006 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.021 0.021 0.008 0.015 0.018 0.015 0.006 0.002 0.003 Zinc mg/L 0.001 20 - 0.76 0.665 0.051 0.522 0.215 0.098 0.099 0.07 0.123 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C Sample Location Drinking Stock Water Date Sampled Water 21/4/09 5/11/09 24/2/10 8/7/10 28/7/11 28/10/11 4/1/12 3/4/12 2/8/12 28/11/12 12/2/13 1/5/13 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.71 6.8 6.82 6.97 6.49 6.85 Electrical conductivity µS/cm 1 - - 720 12400 13200 22007 11031 Total Dissolved Solids mg/L 1 5000* 600b 468 12400 12000 14715 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 444 443 448 118 442 410 398 402 Total Alkalinity as CaCO3 mg/L 1 - - 444 443 448 118 442 410 398 402 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 15 13 18 6 12 9 11 13 Chloride mg/L 1 - 250b 4940 4780 4920 1310 4730 4670 4330 4800 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 615 648 612 103 625 582 594 590 Magnesium mg/L 1 - - 391 396 387 61 386 388 390 388 Sodium mg/L 1 - 180b 1680 1710 1700 755 1660 1620 1650 1700 Potassium mg/L 1 - - 28 24 26 8 26 28 26 28 Total Anions meq/L 0.01 - - 148 144 148 39.4 142 140 130 144 Total Cations meq/L 0.01 - - 137 140 137 43.2 136 132 134 136 Ionic Balance % 0.01 - - 4.15 1.41 3.89 4.55 2.39 2.91 1.46 2.73 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.001 <0.001 0.001 <0.001 <0.001 <0.005 <0.001 Cadmium mg/L 0.001 0.01 - 0.0002 <0.0001 <0.0001 0.0001 <0.0001 0.0003 <0.0005 <0.0001 Chromium mg/L 0.001 1 - <0.001 <0.001 0.003 0.004 0.008 <0.001 <0.005 0.002 Copper mg/L 0.05 1* - 0.007 0.003 0.004 0.005 0.005 0.004 0.008 0.004 Lead mg/L 0.0001 0.1 <0.001 0.001 <0.001 <0.001 0.002 <0.001 0.005 0.001 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.008 0.001 0.004 0.014 <0.005 <0.005 <0.005 <0.001 Zinc mg/L 0.001 20 - 0.018 0.014 0.008 0.372 0.013 0.014 0.036 0.011 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C CD037C Sample Location Drinking Stock Water Date Sampled Water 8/6/13 27/11/13 13/1/14 23/4/14 10/7/14 12/11/14 21/5/15 10/9/15 14/1/16 16/5/16 30/11/16 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters ` pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.15 6.34 6.4 6.4 6.45 6.98 6.48 6.92 7.46 7.44 Electrical conductivity µS/cm 1 - - 11480 12500 13380 10270 16440 15990 13570 13161.3 12500 10800 Total Dissolved Solids mg/L 1 5000* 600b 8680 8230 8759 9000 8120 7020 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 412 418 280 424 425 325 327 326 Total Alkalinity as CaCO3 mg/L 1 - - 412 418 280 424 425 325 327 326 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 18 8 <1 12 <25 14 18 2 Chloride mg/L 1 - 250b 4480 4700 4670 4790 4920 4810 4460 3550 Fluoride mg/L 0.1 <0.1 <0.1 Calcium mg/L 1 1000 - 532 577 481 562 575 528 536 278 Magnesium mg/L 1 - - 373 380 246 368 369 296 325 149 Sodium mg/L 1 - 180b 1500 1780 2000 1640 1690 1520 1790 1870 Potassium mg/L 1 - - 23 24 21 25 27 17 21 20 Total Anions meq/L 0.01 - - 135 141 137 144 147 142 133 107 Total Cations meq/L 0.01 - - 123 138 132 130 133 117 132 108 Ionic Balance % 0.01 - - 4.6 1.06 2.06 4.99 9.7 0.31 0.6 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b 0.002 <0.001 0.001 <0.001 0.001 0.002 <0.001 <0.001 0.002 Cadmium mg/L 0.001 0.01 - 0.0002 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <.0001 <0.0001 0.0001 Chromium mg/L 0.001 1 - 0.004 0.002 0.002 0.002 0.005 <0.001 0.003 0.004 0.005 Copper mg/L 0.05 1* - 0.012 0.005 0.008 0.01 0.015 0.002 <0.001 0.004 0.054 Lead mg/L 0.0001 0.1 0.01 0.002 0.01 0.004 0.011 <0.001 <.001 <0.001 0.005 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 0.002 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.003 0.002 0.004 0.002 0.003 <0.001 <0.001 <0.001 0.002 Zinc mg/L 0.001 20 - 0.052 0.025 0.054 0.028 0.091 0.014 0.018 0.044 0.094 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 Sample Location Drinking Stock Water Date Sampled Water 21/4/09 26/11/09 24/2/10 9/7/10 28/7/11 25/10/11 4/1/12 3/4/12 25/7/12 28/11/12 12/2/13 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.81 7.06 7.11 6.91 6.51 6.71 Electrical conductivity µS/cm 1 - - 17600 27900 18000 22014 27502 Total Dissolved Solids mg/L 1 5000* 600b 11400 21900 13400 14710 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 426 424 419 400 419 349 375 Total Alkalinity as CaCO3 mg/L 1 - - 426 424 419 400 419 349 375 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 22 22 28 34 22 21 21 Chloride mg/L 1 - 250b 10600 10000 9970 9070 10000 7580 7200 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 748 753 695 709 672 522 565 Magnesium mg/L 1 - - 695 664 614 660 626 480 499 Sodium mg/L 1 - 180b 4940 4550 4300 4500 4420 3340 3480 Potassium mg/L 1 - - 46 39 39 42 46 34 33 Total Anions meq/L 0.01 - - 308 291 290 264 291 221 211 Total Cations meq/L 0.01 - - 310 291 273 286 278 212 221 Ionic Balance % 0.01 - - 0.42 0.02 3.01 3.98 2.19 2.2 2.41 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.001 <0.001 <0.005 <0.050 <0.005 <0.005 Cadmium mg/L 0.001 0.01 - 0.0001 0.0001 0.0003 <0.0005 <0.0050 0.0016 0.0006 Chromium mg/L 0.001 1 - 0.001 0.006 <0.001 <0.005 0.016 <0.005 0.006 Copper mg/L 0.05 1* - 0.007 0.005 0.002 0.013 <0.050 0.013 0.017 Lead mg/L 0.0001 0.1 <0.001 <0.001 <0.001 <0.0005 <0.010 <0.005 <0.005 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - <0.005 0.003 0.002 0.009 <0.050 0.021 0.022 Zinc mg/L 0.001 20 - 0.013 0.016 <0.005 0.05 <0.050 0.127 0.177 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 CD056 Sample Location Drinking Stock Water Date Sampled Water 1/5/13 27/11/13 23/4/14 10/7/14 12/11/14 13/1/15 21/5/15 10/9/15 14/1/16 16/5/16 30/11/16 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 MA1 / MA2 coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams coal seams Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.72 6.78 6.76 6.6 6.36 6.96 6.67 7.27 7.32 Electrical conductivity µS/cm 1 - - 19270 25090 26010 25770 20780 25655.8 28200 23200 Total Dissolved Solids mg/L 1 5000* 600b 15985 16631 13550 17000 18300 15100 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 362 354 369 373 401 365 339 321 390 Total Alkalinity as CaCO3 mg/L 1 - - 362 354 369 373 401 365 339 321 390 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 22 23 25 30 26 <25 9 3 18 Chloride mg/L 1 - 250b 8420 7720 8400 9000 9330 9490 10800 10600 7770 Fluoride mg/L 0.1 <0.1 <0.1 Calcium mg/L 1 1000 - 571 557 552 584 654 599 905 862 602 Magnesium mg/L 1 - - 525 524 493 529 604 533 446 571 476 Sodium mg/L 1 - 180b 3750 3530 4310 3860 4430 3870 4050 5340 4690 Potassium mg/L 1 - - 36 32 28 34 34 39 28 34 30 Total Anions meq/L 0.01 - - 245 225 245 262 272 275 312 305 227 Total Cations meq/L 0.01 - - 236 225 256 241 276 243 259 323 274 Ionic Balance % 0.01 - - 1.97 0.01 2.28 4.08 0.76 6.16 9.27 2.81 9.3 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.001 <0.005 <0.001 <0.001 <0.001 <0.001 <0.001 <0.005 0.001 <0.001 Cadmium mg/L 0.001 0.01 - 0.0004 0.0008 <0.001 0.0005 0.0007 0.0002 0.0006 <0.0005 <0.0001 <0.0001 Chromium mg/L 0.001 1 - 0.002 <0.005 0.0006 0.003 0.003 0.002 <0.001 <0.005 0.005 0.002 Copper mg/L 0.05 1* - 0.012 0.013 0.002 0.015 0.006 0.004 0.007 0.007 0.012 0.103 Lead mg/L 0.0001 0.1 <0.001 0.008 0.014 0.004 0.001 0.002 <0.001 <0.005 0.003 <0.001 Mercury mg/L 0.001 0.002 - <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Nickel mg/L 0.005 1 - 0.016 <0.005 0.01 0.016 0.014 0.013 0.013 <0.005 0.004 0.014 Zinc mg/L 0.001 20 - 0.155 0.252 0.005 0.173 0.172 0.107 0.128 0.04 0.042 0.371 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle G1831 Groundwater Quality Data

Parameter Units LORa ANZECC NHMRC CD470 CD476P CD466C CD472 CD382C Sample Location Drinking Stock Water Date Sampled Water 28/6/17 28/6/17 28/6/17 28/6/17 28/6/17

Not defined Not defined Not defined Not defined Not defined Lithology Physical Parameters pH pH Units 0.1 6-8.5 6.5 - 8.5b 6.77 7.85 6.91 7.2 7.22 Electrical conductivity µS/cm 1 - - 27000 35100 28200 31600 24200 Total Dissolved Solids mg/L 1 5000* 600b 17600 22800 18300 20500 15700 Carbonate Alkalinity as CaCO3 mg/L 1 - - <1 <1 <1 <1 <1 Bicarbonate Alkalinity as CaCO3 mg/L 1 - - 359 416 220 321 428 Total Alkalinity as CaCO3 mg/L 1 - - 359 416 220 321 428 Major Ions Sulfate mg/L 1 1000 - 2000 500 / 250b 428 <1 <1 <1 348 Chloride mg/L 1 - 250b 10000 13400 10700 11000 8960 Fluoride mg/L 0.1 Calcium mg/L 1 1000 - 416 437 199 394 446 Magnesium mg/L 1 - - 538 677 685 495 564 Sodium mg/L 1 - 180b 5620 7610 6020 6530 4840 Potassium mg/L 1 - - 30 30 20 28 21 Total Anions meq/L 0.01 - - 298 386 306 317 268 Total Cations meq/L 0.01 - - 310 409 329 345 280 Ionic Balance % 0.01 - - 1.99 2.89 3.54 4.3 2.04 Dissolved Metals Arsenic mg/L 0.01 5 0.2 b <0.005 <0.005 <0.005 <0.005 <0.001 Cadmium mg/L 0.001 0.01 - <0.0005 <0.0005 <0.0005 <0.0005 <0.0001 Chromium mg/L 0.001 1 - <0.005 <0.005 <0.005 <0.005 <0.001 Copper mg/L 0.05 1* - <0.005 <0.005 <0.005 <0.005 <0.001 Lead mg/L 0.0001 0.1 <0.005 <0.005 <0.005 <0.005 <0.001 Mercury mg/L 0.001 0.002 - Nickel mg/L 0.005 1 - 0.006 <0.005 0.011 <0.005 <0.001 Zinc mg/L 0.001 20 - <0.025 <0.025 0.027 0.032 <0.005 Notes: a. Limit of reporting b. Aesthetic guidelines for Drinking Water 0.024 Detected concentration above ANZECC (2000) Stock purposes 0.024 Detected concentration above NHMRC (2011) Drinking Water Guidelines * Concentrations for cattle

Appendix C Summary of DNRME registered bores within a 10 km buffer zone

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | Appendix C

Table C.1 Summary of DNRM existing registered bores within a 10 km buffer zone Screen/perforation/open hole Drilling depth/bottom of Water quality RN Bore name Date drilled SWL (mbGL) Yield (L/s) Aquifer (from... mbGL to... mbGL) strata (mbGL) (µS/cm) 9487 Butchers Bore 13/08/1943 not available 52.7 24.4 0.2 - Westbourne Formation

12144 - 1/01/1952 170.8-202.7 (OH) 202.7 21.3 0.6 Potable Walloon Coal Measures a

16400 Golden Valley Bore 13/11/1965 427-457.5 (P) 457.2 33.5 1.3 6,780 Hutton Sandstone

107260 - 29/03/2000 72-84 (P) 84 50 5.0 - Walloon Coal Measures

123511 - 03/05/2016 520-797 (P) 797 43.5 1.0 Potable Hutton Sandstone

168040 c no data no data no data no data no data no data no data -b

168041 c no data no data no data no data no data no data no data -b

168076 c no data no data no data no data no data no data no data -b

168216 c no data no data no data no data no data no data no data Walloon Coal Measures a

168366 c no data no data no data no data no data no data no data -b

Notes: Table C.1 excludes CSG monitoring bores and VWPs mbGL metres below ground level - no information provided a Aquifer assigned by OGIA b OGIA aquifer attribution is considered to have a low reliability and therefore not presented c 168000 series bores were identified during recent CSG baseline assessments but were not in the Bore database. The bores were validated by OGIA and given a registered number. No publically available data is available other than their location (refer to Section 6.8.3 of the main report)

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix C | 1

Appendix D Bore census (October 2017)

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment Project (G1831) | Appendix D

GROUNDWATER BORE CENSUS

CAMEBY DOWNS COAL MINE 260 RYALLS ROAD, MILES, QLD, 4415

Prepared For: Syntech Resources Pty Ltd Project Number: ENRS0834 Date: 30th October 2017

ENRS PTY LTD ABN 68 600 154 596 T/F 02 9037 4708 M: 0401 518 443 E: [email protected] www.enrs.com.au

Cameby Downs Bore Census Syntech Resources

COMMERCIAL IN CONFIDENCE This document has been prepared consistent with accepted scientific practice, supported by available data and resource conditions, as determined by limited data acquisition during the assessment period, evident at Site at the time. The designated recipients of this report accept all risks and responsibility for losses, damages, costs and other consequences resulting directly or indirectly from using the results of the interpretation, the data, and any information or conclusions drawn from it, whether or not caused by any negligent act or omission. To the maximum permitted by law, ENRS Pty Ltd excludes all liability to any person or identity, arising directly or indirectly from using the information or material contained herein.

INTELLECTUAL PROPERTY LAWS PROTECT THIS DOCUMENT Copyright in the material provided in this document is owned by ENRS Pty Ltd. ENRS reserves the right to revoke this report, its content and results derived during the scope of work. Third parties may only use the information in the ways described in this legal notice:  Temporary copies may be generated, necessary to review the data.  A single copy may be copied for research or personal use.  The documents may not be changed, nor any part removed including copyright notice.  Request in writing is required for any variation to the above.  An acknowledgement to the source of any data published from this document is mandatory.

Author and Document Control

Prepared by: Reviewed by:

Rohan Last Taite Beeston Hydrogeologist & Environmental Scientist Geologist & Environmental Consultant

Record of Distribution

Copies Report No. & File Name Status Date Prepared for:

1 x PDF ENRS0834_Cameby Downs Bore Census Rev.1 25th Oct. 2017 Syntech

1 x PDF ENRS0834_Cameby Downs Bore Census Rev.2 30th Oct. 2017 Syntech

ENRS0834.r2_Cameby Downs Bore Census Page i

Cameby Downs Bore Census Syntech Resources

EXECUTIVE SUMMARY

Environment & Natural Resource Solutions (ENRS Pty Ltd) was commissioned as independent groundwater consultants in September 2017 by Syntech Resources Pty Ltd to complete a bore census for the Cameby Downs expansion project. This groundwater bore census report documents the results of a desktop data review supported by site inspections and meetings with landowners. The report has been prepared with general consideration of the QLD DEHP (2017) minimum requirements for undertaking a baseline assessment on a water bore under Section 413 of the Water Act 2000. The aim of the census was to identify existing bores and groundwater users within the assessment area and where possible conduct site inspections to meet with landholders to verify borehole conditions, and how groundwater is used in the project area. To compile the project results and prepare a database to support the groundwater assessment process. The scope of work for the project comprised the following tasks:  Review of project proposal to delineate the census area;  Desktop review of any previous reports and registered bore records;  Preparation of land owner property maps to support site inspection (summary of available contact details, boundaries, access routes, and potential bore sites);  Landover notification by client to schedule site inspection (Letters, email, meetings or phone calls, as practical);  Site inspections to meet with landowners and inspect bores (if any):  Meet with landowner, review property maps and identify any existing or historical bores;  Record location of any existing bores (easting and northing);  Photograph bore sites;  Gauge base of borehole and depth to groundwater;  Measure borehead gases (if any)  Field measurement of water quality (pH, Temperature, Electrical Conductivity);  Collect representative water samples (where practical) and submit to National Association of Testing Authorities (NATA) accredited laboratory for testing;  Document bore construction, equipment, purpose, and pumping regime;  Compile census results and prepare database; and  Document census methodology, results, and prepare groundwater bore census report. Based on the findings made during the scope of works the following conclusions and recommendations are provided:  A bore census was completed in September-October 2017 and comprised an area of more than 150 square kilometres;

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 The census database combines staged results from desktop reviews, communications with landowners, site inspections and borehead surveys. Supplemented by Driller’s records and registered bore reports;  The project has culminated in a bore census database with records for thirty (30) properties, comprising:  One (1) Stock bore;  Two (2) Monitoring bores; and  Five (5) Decommissioned bores.  The census methodology QA/QC indicators complied with the required standards. Hence, the census results are considered adequate and the quality of the census data is acceptable for further application;  A summary of the census records is tabled in Appendix A with supporting information including survey forms, photographic records, drill logs and decommission reports in Appendix B - Appendix G; and  This report must be read in conjunction with the Statement of Limitations in Section 9.0

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TABLE OF CONTENTS

EXECUTIVE SUMMARY ...... II 1.0 INTRODUCTION ...... 1 1.1 Objectives ...... 1 1.2 Scope of Work ...... 1 1.3 Personnel Qualifications ...... 2 2.0 CENSUS AREA ...... 2 3.0 DESKTOP DATA REVIEW ...... 2 3.1 Previous Reports ...... 2 3.2 Registered Bore Database ...... 2 3.3 Topographic Maps ...... 3 3.4 Aerial Imagery ...... 3 3.5 Landowner Records ...... 3 4.0 CENSUS METHODOLOGY ...... 3 4.1 Land Access Permits ...... 3 4.2 Property Maps ...... 3 4.3 Landowner Meetings ...... 3 4.4 Bore Location Survey ...... 4 4.5 Borehead Photograph ...... 4 4.6 Bore Construction Log ...... 4 4.7 Depth Measurements ...... 4 4.8 Water Quality ...... 4 4.8.1 Gas Screening ...... 4 4.8.2 Field Testing ...... 5 4.8.3 Sampling & Laboratory Analysis ...... 5 5.0 QUALITY ASSURANCE & QUALITY CONTROL ...... 6 5.1 Field Protocols ...... 6 5.2 Laboratory Analytical methods ...... 6 5.3 Data Integrity Assessment ...... 6 5.4 QA/QC Discussion ...... 6 6.0 BORE CENSUS SUMMARY ...... 7 6.1 Registered Bore Records ...... 7 6.2 Landowner Records ...... 7 6.3 Existing Bores (Summary) ...... 7 6.3.1 RN168040 (Syntech Resources) ...... 7 6.3.2 RN168041 (Syntech Resources) ...... 8 6.3.3 RN123511 (Williams J.R.) ...... 8 6.3.4 RN168059 (not locatable) ...... 9 7.0 CONCLUSIONS & RECOMMENDATIONS ...... 9

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8.0 REFERENCES ...... 10 9.0 LIMITATIONS ...... 11

LIST OF TABLES, FIGURES & APPENDICES TABLES Table 1: Field QA/QC ...... 6 Table 2 Data Quality Objectives and Criteria ...... 6

FIGURES Figure 1 Extent of Bore Census Figure 2 Property Homestead Locations Figure 3 Decommissioned Bores Figure 4 Existing Bores

APPENDICES Appendix A Bore Census Database Appendix B RN13602 & RN168216 - Supporting Information Appendix C RN10725 - Supporting Information Appendix D RN12340 - Supporting Information Appendix E RN123511 - Supporting Information Appendix F RN168059 - Supporting Information Appendix G Oxford Downs Windmill - Supporting Information

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1.0 INTRODUCTION

Environment & Natural Resource Solutions (ENRS Pty Ltd) was commissioned as independent groundwater consultants in September 2017 by Syntech Resources Pty Ltd to complete a bore census for the Cameby Downs expansion project. This groundwater bore census report documents the results of a desktop data review supported by site inspections and meetings with landowners. The report has been prepared with general consideration of the QLD DEHP (2017) minimum requirements for undertaking a baseline assessment on a water bore under Section 413 of the Water Act 2000.

1.1 OBJECTIVES The aim of the census was to identify existing bores and groundwater users within the assessment area and where possible conduct site inspections to meet with landholders to verify borehole conditions, and how groundwater is used in the project area. To compile the project results and prepare a database to support the groundwater assessment process.

1.2 SCOPE OF WORK The scope of work for the project comprised the following tasks:  Review of project proposal to delineate the census area;  Desktop review of any previous reports and registered bore records;  Preparation of land owner property maps to support site inspection (summary of available contact details, boundaries, access routes, and potential bore sites);  Landover notification by client to schedule site inspection (Letters, email, meetings or phone calls, as practical);  Site inspections to meet with landowners and inspect bores (if any):  Meet with landowner, review property maps and identify any existing or historical bores;  Record location of any existing bores (easting and northing);  Photograph bore sites;  Gauge base of borehole and depth to groundwater;  Measure borehead gases (if any)  Field measurement of water quality (pH, Temperature, Electrical Conductivity);  Collect representative water samples (where practical) and submit to National Association of Testing Authorities (NATA) accredited laboratory for testing;  Document bore construction, equipment, purpose, and pumping regime;  Compile census results and prepare database; and

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 Document census methodology, results, and prepare groundwater bore census report.

1.3 PERSONNEL QUALIFICATIONS The bore census was undertaken by experienced personnel with tertiary qualifications in Hydrogeology, supported by professional technical staff. As required by the QLD DEHP (2017) minimum requirements for undertaking a baseline assessment, the supervising Hydrogeologist has attained more than two (2) years experience in groundwater level monitoring and sampling, including monitoring of water levels in bores equipped with pumping infrastructure, and has practical knowledge of water bore construction infrastructure.

Position Name Qualification/Experience

Supervising Rohan Last BSc (2000), MSc Hydrogeology (2004) Hydrogeologist >15 years drilling, sampling & monitoring exp.

Supporting Helen Cole >6 years environmental experience. Personnel

Considerable assistance was also received from landowners who provided borehole information and their time to locate and inspect bores.

2.0 CENSUS AREA

The extent of the bore census was selected to encompass an adequate buffer around the project area and extends approximately five (5) kilometres south and southwest of the Mine Lease (ML). The census area comprises 150 square kilometres as depicted in Figure 1.

3.0 DESKTOP DATA REVIEW

Preparation of the census database included the review and collation of information from various data sources including:

3.1 PREVIOUS REPORTS No publicly accessible previous reports were available for review at the time of this assessment. However, ENRS understand the area has likely been the subject of baseline assessments by the Coal Seam Gas (CSG) industry.

3.2 REGISTERED BORE DATABASE A search of the registered groundwater bore database maintained by the QLD Queensland Department of Natural Resources and Mines (DNRM) (2012) was conducted. Where available, data includes summary reports on bore location,

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construction, geology, and aquifer details as derived from Drillers Logs. The database is commonly inaccurate or contains limited data.

3.3 TOPOGRAPHIC MAPS The location of windmills, pumps and bores is often marked with symbols on the topographic map sheets. The location of these symbols may be digitised to assist with identifying potential bore sites;

3.4 AERIAL IMAGERY A search of online imagery from QLD globe and google earth was conducted to assist with the preparation of property maps. Imagery was inspected to validate the presence and location of groundwater sites, infrastructure, access routes and boundaries.

3.5 LANDOWNER RECORDS Valuable information may be provided by landowners, including details of historical and existing bores (if any), construction logs; equipment and pumping regimes; yield and water quality;

4.0 CENSUS METHODOLOGY

4.1 LAND ACCESS PERMITS Prior to census inspections landowners were notified by the client to ensure the necessary approvals and permits were in place. No properties were accessed outside the approved times.

4.2 PROPERTY MAPS Prior to census inspections individual property maps were prepared utilising existing data sources to map all potential bore sites. The maps provided a valuable tool to direct site inspections and confirm which bores were actually present on the ground. It is noted than many bores mapped from the registered bore database were confirmed not to exist during landowner meetings.

4.3 LANDOWNER MEETINGS Upon arrival at each property the bore census team met with the landowner to provide an overview of the process and document information provided by the landowner. The property map was annotated with the assistance of the landowner to confirm which bores were present or did not exist. Sites were then visited to ground truth their location and survey the bore details and water quality. Feedback obtained from the landowners was incorporated into the database where relevant.

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4.4 BORE LOCATION SURVEY The location of each bore inspected was surveyed by ENRS using a hand-held GPS to record the easting and northing. In general, a hand-held unit is expected to be accurate to within five (5) metres where supported by sufficient satellite coverage. Records were saved digitally by ENRS within the GPS unit and recorded manually on designated field sheets.

4.5 BOREHEAD PHOTOGRAPH Digital photos were taken at each bore census site with the GPS location embedded within the file. Multiple photos were taken to record the bore head and surrounding infrastructure, if any. Where the bore was equipped the photo frame was set to include the complete infrastructure.

4.6 BORE CONSTRUCTION LOG A key aim of the census was to document the bore construction at each site. Where available a copy of the Driller’s Log was provided by the landowner. Where a Log was not available, the existing bore details, namely: location; depth; age and construction, were applied to correlate this site data with a registered bore number. Where the available information confirmed the correlation with a registered number the database summary report was utilised to provide additional details of bore construction.

4.7 DEPTH MEASUREMENTS Where the bore condition and equipment provided down hole access, the depth of the bore was gauged using a groundwater dipper. The dipper comprised a metre tape reel with a weighted probe. The probe is approximately 12mm in diameter, however in the majority of situations where a bore is equipped with a pump it is not possible to insert the dipper into the bore as either: (1) the bore head is sealed; (2) there is insufficient access; or (3) there is a high risk that the dipper will become entangled between the pump column and electrical cables which may require removing the entire pump column. Field notes were made where access was restricted or the depth of the bore and groundwater level could not be gauged. The depth to groundwater (DTW) was gauged and recorded in designated field sheets. The stick-up height of the bore casing above ground level was measured and recorded to facilitate an accurate calculation of the groundwater depth relative to ground level.

4.8 WATER QUALITY

4.8.1 Gas Screening Prior to opening of any borehead fastening, a calibrated multigas probe should be prepared to obtain a sample of gas readings inside the borehead and prior to any purging or disturbance. Where practical levels are recorded for concentrations of

CH4, H2S, CO, and O2. Where elevated levels are observed, further water quality sampling for dissolved gases may be required.

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4.8.2 Field Testing Groundwater quality is tested in the field where conditions permit access. Sampling is conducted by the preferred methods in the following order: 1. Existing pump operated to purge bore by removing at least three (3) to five (5) bore volumes prior to collection of sample; 2. Existing pump operated to purge bore for as long as practical prior to collecting sample; 3. Bailer lowered manually in unequipped bores to collect grab sample; and 4. Sample obtained from tap or break in pump line. Field testing is conducted immediately after sampling to record physical water parameters. A multi-probe water quality meter is used to measure the following parameters:  Temperature;  Electrical Conductivity (Salinity - EC);  pH (Acidity); and  Oxygen reduction potential (Redox / Eh). Electrical Conductivity (EC) provides a measure of the total concentration of ion species and is widely used to assess the levels of dissolved salts in water (salinity). In general, drinking water is less than 800 µS/cm whilst sea water is 56,000 µS/cm. Salinity was measured in the field during site inspections between a minimum of 462 µS/cm and a maximum of 11,330 µS/cm. Potential Hydrogen (pH) determines the balance between positive hydrogen ions (H+) and negative hydroxyl ions (OH-) and provides a test of water acidity (low pH) or alkalinity (high pH). Most natural freshwaters have a pH in the range 6.5 to 8.0 (ANZECC 2000) although groundwater can vary significantly due to bore construction and the host geology.

4.8.3 Sampling & Laboratory Analysis Groundwater samples are collected from selected bores where adequate purging is practical to obtain a representative sample. Groundwater samples for dissolved metal analysis are field filtered, using a disposable 0.45 µm membrane filter, prior to collection in acid preserved containers. Samples are sealed in laboratory prepared sampling containers appropriate for the analysis and clearly labelled with the sample identification. All samples are stored on ice immediately after their collection and transported to the laboratory under Chain of Custody (COC) documentation in accordance with AS:5667 Sampling of Groundwaters (1998). A NATA registered laboratory is contracted to undertake the laboratory analysis in accordance with the NATA approved methods.

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5.0 QUALITY ASSURANCE & QUALITY CONTROL

5.1 FIELD PROTOCOLS

The Quality Assurance and Quality Control (QA/QC) protocols used during the census fieldwork are shown below in Table 1.

Table 1: Field QA/QC

Protocol Description Personnel comprised qualified Hydrogeologists & technical Census Team staff trained in conducting groundwater bore surveys. Bore data recorded both manually in designated field sheets Field Records and digitally. Sample All field testing equipment calibrated prior to operation. Equipment Sample equipment decontaminated between sample sites. Chain of Custody All samples (if any) logged and transferred under appropriately Forms completed Chain of Custody (COC) forms.

5.2 LABORATORY ANALYTICAL METHODS Analysis of samples is conducted by a NATA accredited laboratory. QA/QC results are reported in the Laboratory Certificates of Analysis.

5.3 DATA INTEGRITY ASSESSMENT Where available this borehole data assessment has utilised formal sources of information issued by government. These formal sources are supplemented by information provided by the client, landowner, and observations made by ENRS professionals during site inspections. Review and comparison of the groundwater records is conducted to assess for and identify any significant data gaps or inconsistencies to trigger further investigations. Hence, the sources and content of this assessment maybe considered to provide a reliable and satisfactory level of accuracy to support this record of groundwater bores.

5.4 QA/QC DISCUSSION The QA/QC indicators complied with the required standards. It is therefore concluded that the QA/QC results are adequate, and the quality of the census data is acceptable for use. A summary of the Data Quality performance is provided in Table 2.

Table 2 Data Quality Objectives and Criteria Data Quality Evaluation Criteria Status Objective (DQO) Documentation Completion of field records, equipment calibration, completeness Site photos. 

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Data Quality Evaluation Criteria Status Objective (DQO) Use of appropriate techniques for gauging, Data comparability sampling, storage and transportation of samples.  Use of NATA certified laboratory (if any). Data Census inspection covered all areas of concern representativeness within and surrounding the project area.  Experienced and qualified field personnel. Precision & Appropriate field techniques & calibrated accuracy  equipment

6.0 BORE CENSUS SUMMARY

6.1 REGISTERED BORE RECORDS The desktop review identified six (6) bore registration records within the census area. The census was subsequently extended to encompass an additional two (2) adjoining 168XXX series and one (1) 123XX series bore located south of the census area.  Two (2) of these registered bores were confirmed to be the same borehole which has been decommissioned (RN13602 & RN168216). A copy of the decommission Form PA-40 is provided in Appendix B;  Five (5) bores were assessed to have been decommissioned, including the duplicate bores; and  Two (2) bores were identified as Monitoring bores; and  One (1) bore could not be located (168059). No homestead was present and the landowner was unknown. No bore infrastructure was visible as viewed from the roadside.

6.2 LANDOWNER RECORDS Information received from landowners during on site property visits and through correspondence received by Syntech, confirmed twenty (20) properties in the census area do not contain groundwater bores. During site inspections and landowner meetings, two (2) existing bores were identified which had not previously been reported during the desktop review of registered bore records. A summary of the existing bores is provided in the following Section.

6.3 EXISTING BORES (SUMMARY) The census identified the following existing bores:

6.3.1 RN168040 (Syntech Resources) The bore is situated on lands owned by the client and was not inspected during the census. The project Environmental Officer confirmed the bore is located at an existing groundwater monitoring point. Only one bore is understood to be present at this

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monitoring point. Hence, bore RN168040 is assessed to be monitoring bore CD036R. The reader is referred to client records for monitoring data at the site.

6.3.2 RN168041 (Syntech Resources) The bore is situated on lands owned by the client and was not inspected during the census. The project Environmental Officer confirmed the bore is located at an existing groundwater monitoring point. Only one bore is understood to be present at this monitoring point. Hence, bore RN168041 is assessed to be monitoring bore CD018. The reader is referred to client records for monitoring data at the site.

6.3.3 RN123511 (Williams J.R.) The census team met with the landowner of title 72/BWR188 on the 28th September 2017 with the objective to confirm the status of RN12340 registered at the site. During the meeting the landowner confirmed RN12340 had been decommissioned and replaced with RN123511. A decommission and replacement bore report was cited incorporating drillers log, laboratory results, pump test, geophysical composite log and pump equipment. Copies of available records are provided in Appendix E and summarised in the following table: Bore Registration No. 123511 (drillers work ref no. 572874) Year Drilled 2016 Land Parcel 72 / BWR188 Easting (UTM Zone 56) 237467.62 Northing 7040134.76 Purpose Stock Casing 1.5-148m (244.47mm OD Steel 1.5-538m (177.80mm OD Steel) Water Entry 520-797m (114.3mm OD Steel 15mm slots) Depth of Bore 797 metres Depth to Groundwater ~20m from composite log Yield Pumped at 1L/s for 16 hours Water Quality - Salinity 2,888µS/cm (2,350mg/L) after pump test; - Major chemistry High levels of fluoride reported by laboratory; - Gas Gas detected during drilling. Borehead works fitted with vacuum breaker to vent gas. Equipment Submersible pump capacity of 0.5L/s set at 60m. Solar panels with pumping on demand to Turkeys Nest Dam.

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6.3.4 RN168059 (not locatable) Census personnel visited Gospers Road on the 11th October 2017 with the aim to inspect the registered location of RN168059. The registered position is approximately 1,200 metres south of Gospers Road in an open paddock, no bore infrastructure was visible. During the inspection contact was made with a contractor working on the adjacent land parcel to the east (Oxford Downs). The contractor indicated an old Windmill is present on Oxford Downs. The Windmill was viewed by census personnel from Gospers Road. Oxford Downs is leased by QGC to Stanbroke Pastoral. Subsequent telephone correspondence with the manager of Stanbroke Pastoral (pers comm.27/10/2017) confirms the property is serviced by Creek water and no active groundwater bores are utilised at the property. Hence, the Windmill is assessed not to be an active bore and no further assessment is required. A summary of the site inspection records is provided in Appendix G. The manager of Stanbroke Pastoral also confirmed there are no bores on the property where RN168059 is registered. In, summary no bores were identified during the census in proximity to RN168059. Census records are provided in Appendix F.

7.0 CONCLUSIONS & RECOMMENDATIONS

Based on the findings made during the scope of works the following conclusions and recommendations are provided:  A bore census was completed in September-October 2017 and comprised an area of more than 150 square kilometres;  The census database combines staged results from desktop reviews, communications with landowners, site inspections and borehead surveys. Supplemented by Driller’s records and registered bore reports;  The project has culminated in a bore census database with records for thirty (30) properties, comprising:  One (1) Stock bore;  Two (2) Monitoring bores; and  Five (5) Decommissioned bores.  The census methodology QA/QC indicators complied with the required standards. Hence, the census results are considered adequate and the quality of the census data is acceptable for further application;  A summary of the census records is tabled in Appendix A with supporting information including survey forms, photographic records, drill logs and decommission reports in Appendix B - Appendix G; and  This report must be read in conjunction with the Statement of Limitations in Section 9.0

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8.0 REFERENCES

ANZECC and ARMCANZ, 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Artarmon: Australian Water Association. Committee CE/28, 1990. AS2368—1990 Test pumping of water wells, Sydney: Standards Australia. Department of Environment and Heritage Protection, 2017. Guideline Baseline Assessments Department of Environment and Heritage Protection, 2013. Monitoring and Sampling Manual 2009—Environmental Protection (Water) Policy 2009, Brisbane: Queensland Government. Department of Natural Resources and Mines, 2011. Code of practice for coal seam gas well head emissions detection and reporting, Brisbane: Department of Natural Resources and Mines. Department of Primary Industries, 1982. Farm management handbook. 6th ed. Brisbane: Department of Primary Industries. Environment Protection Authority, 2007. Regulatory monitoring and testing—Groundwater sampling, Adelaide: Environment Protection Authority. Joint Technical Committee EV/8, 2016. AS/NZS 5667:11 1998 Water quality - Sampling - Guidance on sampling of groundwaters, Sydney: Standards Australia. National Health and Medical Research Council, 2011. Australian Drinking Water Guidelines, Canberra: Commonwealth of Australia. National Uniform Drillers Licensing Committee, 2012. Minimum construction requirements for water bores in Australia, 3rd edition. Sundaram, B. et al., 2009. Groundwater Sampling and Analysis—A Field Guide, Canberra: Commonwealth of Australia.

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9.0 LIMITATIONS

This report and the associated services performed by ENRS are in accordance with the scope of services set out in the contract between ENRS and the Client. The scope of services was defined by the requests of the Client, by the time and budgetary constraints imposed by the Client, and by the availability of access to Site. ENRS derived the data in this report primarily from visual inspections, and, limited sample collection and analysis made on the dates indicated. In preparing this report, ENRS has relied upon, and presumed accurate, certain information provided by government authorities, the Client and others identified herein. The report has been prepared on the basis that while ENRS believes all the information in it is deemed reliable and accurate at the time of preparing the report, it does not warrant its accuracy or completeness and to the full extent allowed by law excludes liability in contract, tort or otherwise, for any loss or damage sustained by the Client arising from or in connection with the supply or use of the whole or any part of the information in the report through any cause whatsoever. Limitations also apply to analytical methods used in the identification of substances (or parameters). These limitations may be due to non-homogenous material being sampled (i.e. the sample to be analysed may not be representative), low concentrations, the presence of ‘masking’ agents and the restrictions of the approved analytical technique. As such, non-statistically significant sampling results can only be interpreted as ‘indicative’ and not used for quantitative assessments. The data, findings, observations, conclusions and recommendations in the report are based solely upon the state of Site at the time of the investigation. The passage of time, manifestation of latent conditions or impacts of future events (e.g. changes in legislation, scientific knowledge, land uses, etc) may render the report inaccurate. In those circumstances, ENRS shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of the report. This report has been prepared on behalf of and for the exclusive use of the Client, and is subject to and issued in connection with the provisions of the agreement between ENRS and the Client. ENRS accepts no liability or responsibility whatsoever and expressly disclaims any responsibility for or in respect of any use of or reliance upon this report by any third party or parties. It is the responsibility of the Client to accept if the Client so chooses any recommendations contained within and implement them in an appropriate, suitable and timely manner.

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Figures

Figure 1 Extent of Bore Census

QLD DNRM Registered Bore Database

Figure 2 Property Homestead Locations

Legend Census Letter Delivered Landowner Meeting Landowner Correspondence to Syntech

Figure 3 Decommissioned Bores

Figure 4 Existing Bores

APPENDICES

Appendix A

Bore Census Database

BORE CENSUS DATABASE: CAMEBY DOWNS

Line Year BORE Y/N Bore RN East Z56 North Use Status Depth SWL Address Property Landholder Title Communications Item Drilled 1 No 10725 231129 7046551 Decommissioned 1946 171.4 N/A Stockroute Lane N/A Williams (Robert) 45/BWR107 29/9 ENRS meeting with landowner, confirmed no bores on property or in adjoining areas. Previous bore was unsuccessful and later Decommissioned by QGC. E/N updated by ground truthing. Registered location incorrect.

2 No 12340 238129 7039797 Decommissioned 1953 346.3 N/A Weir Road Columboola Williams (JR) 72/BWR188 28/9 ENRS meeting with landowner, confirmed Brafords / bore 12340 (drillled 1953) Decommissioned by McNulty QGC and replacement bore drilled RN123511. Complete bore report cited with lab, geophys, pump spec. Bore inspected, no access for field testing. Refer to QGC report.

3 No 13602 & 232580 7051302 Decommissioned 1958 384 N/A Kerwicks Road, 290. N/A Orchard-Lisle and 71/BWR159 Email sent to Amanda Reed on 29 August 168216 (Decommission Hookswood Powell (Jolyon and 2017 by DMJ. RN13602 also licensed under Form PA-40) Kate) RN168216. Decommission form PA-40 completed by Arrow Energy 19/07/2017.

4 No 13548 229443.91 7049070.04 Decommissioned 1958 130.4 N/A Warrego Hwy N/A N/A 2/SP214566 Registered by DNRM as Decommissioned.

5 Yes 123511 237467.62 7040134.76 Stock 2016 797 N/A Weir Road, 208 Columboola Williams (JR) 72/BWR188 28/9 ENRS met with landowner, confirmed Brafords / bore 12340 Decommissioned by QGC and McNulty replacement bore drilled RN123511. Complete bore report cited with lab, geophys, pump spec. Bore inspected, no access for field testing. Refer to QGC report.

6 Yes 168040 234986 7052738 Monitoring N/A N/A N/A Ryalls Road N/A Syntech Resources 1/RP893208 Review of site plans indicates 168040 is (CD036R) Pty Ltd CD036R at similar location. 7 Yes 168041 237873 7049657 Monitoring N/A N/A N/A Ryalls Road N/A Syntech Resources 3/RP893208 Review of site plans indicates 168041 is (CD018) Pty Ltd CD018 at similar location. 8 N/A 168059 239015 7041211 N/A N/A N/A N/A Gospers Road N/A N/A 67/BWR96 11/10/2017. No bore visible viewed from Gospers Rd by Yancoals H.C. No landower details or homestead. Telephone call by H.C. 25/10/17 with adjacent land manager confirms no bores on property where 168059 is registered. 9 No 168075 243789 7044666 Decommissioned N/A N/A N/A Goombi Road, 195 Kooringa Brennan (Kevin) 42/BWR74 28/9 ENRS meeting with landowner, no bores on property. Landowner confirmed with client bore was previously Decommissioned.

10 No N/A 239235 7042052 Not Used N/A N/A N/A Gospers Road Oxford Downs Stanbroke Pastoral 66/BWR96 11/10/2017 Old Windmill viewed from Gospers (Tony Roseby) - 0437 Road by Yancoals H.C. No bore records 754 558 available. Stanbroke Pastoral hold a 10yr lease from QGC. Telephone call by H.C. 25/10/17 with manager confirms property is supplied by Creek water with no active bores.

11 No ------Brownlies Road, 74 N/A Aird (Malcolm & Ruth) 109/BWR391 28/9 ENRS meeting with landowner, confirmed no bores in area. Only bore he knew of was north of hwy in former US military camp.

12 No ------C Kerrs Road N/A Baes (Chris) 5/BWR149 ENRS letter drop 28/9 and follow up visit 29/9, previously Adermann no one home. Alan Andrews email to RS property 19/10/2017. Richard Webb had a conversation with Steve Davies, the owner prior to Adermann who confirmed there are no water bores on the property. 13 No ------Columboola Stock Rte T-Bone Belleville (Rodney) 44/BWR107 28/9 ENRS meeting with landowner, confirmed Downs no bores on property or in adjoining areas.

14 No ------Brownlies Road, 22 N/A Beutel (Allan) 204/C5742 28/9 ENRS meeting with landowner, confirmed no bores on property or in adjoining areas.

15 No ------Davies Road, 395 N/A Davies (Carmel) 12/BWR149 email AH to LB 24/8/2017. Roffe; Poulsen; & Davies – client discussion with landowners indicates these properties do not have bores.

16 No ------Boort Koi Road, 25 NA Department of 10/N25510 28/9 ENRS site meeting with green keeper, Education and confirmed no bores. Rain water tanks only. Training Noted former US Military bore on adjoining lands. Email from School Principal 3/10/17 confirms no bores present.

17 No ------Brownlies Road, 23 N/A Donaldson (Penelope 5/SP131623 site visit 28/9 not home. 29/9 ENRS meeting Leonard) with landowner, confirmed no bores on property or in adjoining areas. 18 No ------Warrego Hwy, 29345 Kakody Grealy (Sharon) 131/BWR794 site visit 28/9 not home. 29/9 ENRS meeting with landowner, confirmed no bores on property or in adjoining areas. 19 No ------Warrego Hwy, 2953 Boolabri Guymer & Embry 2/RP121117 Letter drop by Richard Webb 30/8/17. ENRS Downs (John and Joanna) Site visit 28/9 not home. 29/9 ENRS meeting with landowner, confirmed no bores on property or in adjoining areas. 20 No ------Warrego Hwy, 29622, N/A Johnson (Ian and 672/RP897022 Letter drop by Richard Webb 30/8/17. ENRS Columboola Violet) Site visit 28/9 not home. 29/9 ENRS meeting with landowner, confirmed no bores on property or in adjoining areas. 21 N/A ------Brownlies Road, 319 Wongalea McDiarmid 32/BWR106 ENRS letter drop 28/9 and follow up visits 29/9 and 11/10/17. Not home. 22 No ------Warrego Hwy, 29319 N/A Newton (Alfred & 10/C5741 site visit 28/9 not home. 29/9 ENRS meeting Margaret) with landowner, confirmed no bores on property or in adjoining areas. 23 N/A ------Brownlies Road, 322 N/A O'Kelly & Beynon 42/BWR107 ENRS letter drop 28/9 and follow up visits 29/9, and 11/10/2017. Not home. As viewed from front gate, a water pump is visible adj house, could be from dam or bore.

24 No ------Davies Road, 29. N/A Poulsen (Raymond & email AH to LB 24/8/2017. a. Roffe; Poulsen; Goombi Francis) and Davies – Alan said he understands that 33/BWR149 these properties do not have bores/wells.

25 N/A ------Warrego Hwy Fermoy QGC Pty Limited 58/BWR94 Not visited by ENRS at request of client 26 N/A ------Kerwicks Road N/A Roffe (Craig) 73/BWR294 Not visited by ENRS at request of client 27 No ------Warrego Hwy, 28763 N/A Searle (Dale & 56/BWR562 28/9 Not Home. Letter Drop. Emails from Dianna) client indicate no bores present. 28 No ------Warrego Hwy, 29504 Stockwhip Stockwhip Future 66/BWR154 ENRS letter drop 28/9 and follow up visit 29/9, Future Park Park Pty Ltd Not home. Email from client 19/10 Property Agent confirms no bores. 29 No ------Boort Koi Road, 43 N/A Syntech Resources 607/C5744 ENRS meeting with green keeper from Pty Ltd adjoining DoE site 28/9, indicates no bores on properties 30 N/A ------Kerwicks Road N/A Young ENRS letter drop 28/9 and follow up visits 29/9 68/BWR179 and 11/10/17. Not home. Project No.: ENRS0834 Updated 30/10/2017

Appendix B

RN13602 & RN168216 - Supporting Information

Appendix C

RN10725 - Supporting Information

FIELD SURVEY FORM: GROUNDWATER BORE CENSUS SURVEY SURVEY BORE ID: DATE:  PERSONNEL: 3-

)$ 

PROPERTY DETAILS Property Name: /" Property Address: Land Owner: 8JMMJBNT
3PCFSU 4UPDLSPVUF
-BOF

BORE DETAILS Local Bore Name: /" Licence Number: %FDPNNJTTJPOFE Easting (GDA94):  Ref No/GW Number:  Northing:  GPS Elevation: /" CONSTRUCTION SUMMARY Bore Depth (mBTOC):  Year Drilled:  Casing Stick Up (SU): /" Casing type/ID: /" Construction Summary (Driller, Drilled Depth, Diameter, Aquifer Intercepts, Yield, Screen Interval, seal/grout…...): /"

WATER LEVEL INFORMATION Depth to Water (mBTOC): /" Date / Time of Measurement: Time Since Pump Ceased (Hr/Days):

WATER USAGE / PUMP DETAILS Bore in Use Y/N: %FDPNNJTTJPOFE Equipment/Type/condition: Purpose: Stock Domestic Irrigation Commercial/Industrial Recreation Mining Town Water Other:

Pump Intake Depth: Pump Regime (Hrs per Day / Vol):

Pump Rate (L/s or GPH): Flow Rate: Measured: Y / N

Stock type & No.: Irrigation Crop / Area:

Lic. No. / Allocation (ML/Yr): Storage Type / Volume : Tanks Dams

SAMPLE DETAILS

Well Head Gas Screening: CH4: H2S: CO: O2:

Vol. removed (min. 3): Bailer / Pump / Tap / Purged: Y / N Submitted to Lab.: Y / N Or duration for WQ to stabilise: Tank / Other………

EC Actual: (mS or μS/cm) mg Temp: pH: ORP: DO: Specific: (mS or μS/cm) %

COMMENTS .FU
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Appendix D

RN12340 - Supporting Information

FIELD SURVEY FORM: GROUNDWATER BORE CENSUS SURVEY SURVEY BORE ID: DATE:  PERSONNEL: 3-

)$ 

PROPERTY DETAILS Property Name: /" Property Address: Land Owner: 8JMMJBNT
+3 8FJS
3PBE

BORE DETAILS Local Bore Name: /" Licence Number: %FDPNNJTTJPOFE Easting (GDA94):  Ref No/GW Number:  Northing:  GPS Elevation: /" CONSTRUCTION SUMMARY Bore Depth (mBTOC):  Year Drilled:  Casing Stick Up (SU): /" Casing type/ID: /" Construction Summary (Driller, Drilled Depth, Diameter, Aquifer Intercepts, Yield, Screen Interval, seal/grout…...): 3FGFS
UP
#PSF
$BSE
3FQPSU
BUUBDIFE

WATER LEVEL INFORMATION Depth to Water (mBTOC): /" Date / Time of Measurement: Time Since Pump Ceased (Hr/Days):

WATER USAGE / PUMP DETAILS Bore in Use Y/N: %FDPNNJTTJPOFE Equipment/Type/condition: Purpose: Stock Domestic Irrigation Commercial/Industrial Recreation Mining Town Water Other:

Pump Intake Depth: Pump Regime (Hrs per Day / Vol):

Pump Rate (L/s or GPH): Flow Rate: Measured: Y / N

Stock type & No.: Irrigation Crop / Area:

Lic. No. / Allocation (ML/Yr): Storage Type / Volume : Tanks Dams

SAMPLE DETAILS

Well Head Gas Screening: CH4: H2S: CO: O2:

Vol. removed (min. 3): Bailer / Pump / Tap / Purged: Y / N Submitted to Lab.: Y / N Or duration for WQ to stabilise: Tank / Other………

EC Actual: (mS or μS/cm) mg Temp: pH: ORP: DO: Specific: (mS or μS/cm) %

COMMENTS .FU
XJUI
MBOEPXOFS
$POGJSNFE

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SUPPORTING Meeting with Land Manager Government Log Drillers Log Water Sample Photo 9 INFORMATION 9 9

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Page 1

Page 2

Page 3

Page 4

Page 5

Page 6

Appendix E

RN123511 - Supporting Information

FIELD SURVEY FORM: GROUNDWATER BORE CENSUS SURVEY SURVEY BORE ID: DATE:  PERSONNEL: 3-

)$ 

PROPERTY DETAILS Property Name: /" Property Address: Land Owner: 8JMMJBNT
+3 8FJS
3PBE

BORE DETAILS Local Bore Name: /" Licence Number:  Easting (GDA94):  Ref No/GW Number:  Northing:  GPS Elevation: /" CONSTRUCTION SUMMARY Bore Depth (mBTOC):  Year Drilled:  Casing Stick Up (SU): /" Casing type/ID: /" Construction Summary (Driller, Drilled Depth, Diameter, Aquifer Intercepts, Yield, Screen Interval, seal/grout…...): 3FGFS
UP
%SJMMFST
-PH
BUUBDIFE

WATER LEVEL INFORMATION Depth to Water (mBTOC): /" Date / Time of Measurement: Time Since Pump Ceased (Hr/Days):

WATER USAGE / PUMP DETAILS Bore in Use Y/N: :FT Equipment/Type/condition: TVCNFSTJCMF Purpose: Stock 9 Domestic Irrigation Commercial/Industrial Recreation Mining Town Water Other: Pump Intake Depth: N Pump Regime (Hrs per Day / Vol): PO
EFNBOE Pump Rate (L/s or GPH): -T Flow Rate: _-T Measured: Y / N Stock type & No.: /" Irrigation Crop / Area: /" Lic. No. / Allocation (ML/Yr): /" Storage Type / Volume : Tanks /" Dams

SAMPLE DETAILS

Well Head Gas Screening: CH4: H2S: CO: O2:

Vol. removed (min. 3): Bailer / Pump / Tap / Purged:  Y / N Submitted to Lab.: Y / N Or duration for WQ to stabilise: Tank / Other……… 

EC Actual:  




 (mS or μS/cm) mg Temp: pH: ORP: DO: Specific: (mS or μS/cm) %

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Page 1 of 1

Appendix F

RN168059 - Supporting Information

FIELD SURVEY FORM: GROUNDWATER BORE CENSUS SURVEY SURVEY BORE ID: DATE:  PERSONNEL: )$ 

PROPERTY DETAILS Property Name: /" Property Address: Land Owner: /" (PTQFST
3PBE

BORE DETAILS Local Bore Name: /" Licence Number: /" Easting (GDA94):  Ref No/GW Number:  Northing:  GPS Elevation: /" CONSTRUCTION SUMMARY Bore Depth (mBTOC): /" Year Drilled: /" Casing Stick Up (SU): /" Casing type/ID: /" Construction Summary (Driller, Drilled Depth, Diameter, Aquifer Intercepts, Yield, Screen Interval, seal/grout…...): /"

WATER LEVEL INFORMATION Depth to Water (mBTOC): /" Date / Time of Measurement: Time Since Pump Ceased (Hr/Days):

WATER USAGE / PUMP DETAILS Bore in Use Y/N: /" Equipment/Type/condition: Purpose: Stock Domestic Irrigation Commercial/Industrial Recreation Mining Town Water Other:

Pump Intake Depth: Pump Regime (Hrs per Day / Vol):

Pump Rate (L/s or GPH): Flow Rate: Measured: Y / N

Stock type & No.: Irrigation Crop / Area:

Lic. No. / Allocation (ML/Yr): Storage Type / Volume : Tanks Dams

SAMPLE DETAILS

Well Head Gas Screening: CH4: H2S: CO: O2:

Vol. removed (min. 3): Bailer / Pump / Tap / Purged: Y / N Submitted to Lab.: Y / N Or duration for WQ to stabilise: Tank / Other………

EC Actual: (mS or μS/cm) mg Temp: pH: ORP: DO: Specific: (mS or μS/cm) %

COMMENTS 5IF
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SUPPORTING Meeting with Land Manager 9 Government Log Drillers Log Water Sample Photo INFORMATION

Bore Census Form.v1701 PAGE _____











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Appendix G

Oxford Downs Windmill - Supporting Information

FIELD SURVEY FORM: GROUNDWATER BORE CENSUS SURVEY SURVEY BORE ID: DATE:  PERSONNEL: )$ /"

PROPERTY DETAILS Property Name: /" Property Address: Land Owner: /" (PTQFST
3PBE
0YGPSE
%PXOT
1SPQFSUZ

BORE DETAILS Local Bore Name: /" Licence Number: /" Easting (GDA94):  Ref No/GW Number: /" Northing:  GPS Elevation: /" CONSTRUCTION SUMMARY Bore Depth (mBTOC): /" Year Drilled: /" Casing Stick Up (SU): /" Casing type/ID: /" Construction Summary (Driller, Drilled Depth, Diameter, Aquifer Intercepts, Yield, Screen Interval, seal/grout…...): /"

WATER LEVEL INFORMATION Depth to Water (mBTOC): /" Date / Time of Measurement: Time Since Pump Ceased (Hr/Days):

WATER USAGE / PUMP DETAILS Bore in Use Y/N: /P Equipment/Type/condition: Purpose: Stock Domestic Irrigation Commercial/Industrial Recreation Mining Town Water Other:

Pump Intake Depth: Pump Regime (Hrs per Day / Vol):

Pump Rate (L/s or GPH): Flow Rate: Measured: Y / N

Stock type & No.: Irrigation Crop / Area:

Lic. No. / Allocation (ML/Yr): Storage Type / Volume : Tanks Dams

SAMPLE DETAILS

Well Head Gas Screening: CH4: H2S: CO: O2:

Vol. removed (min. 3): Bailer / Pump / Tap / Purged: Y / N Submitted to Lab.: Y / N Or duration for WQ to stabilise: Tank / Other………

EC Actual: (mS or μS/cm) mg Temp: pH: ORP: DO: Specific: (mS or μS/cm) %

COMMENTS 3PBETJEF
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SUPPORTING Meeting with Land Manager Government Log Drillers Log Water Sample Photo INFORMATION 9

Bore Census Form.v1701 PAGE _____











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Appendix E Cameby Downs Continued Operations Project – Numerical Modelling Report

Australasian Groundwater and Environmental Consultants Pty Ltd Cameby Downs Continued Operations Project – Groundwater Impact Assessment (G1831) | Appendix E Cameby Downs Continued Operations Project Numerical Modelling Report

E1 Introduction and objectives

Numerical modelling was undertaken to assess the impact of the proposed Cameby Downs Continued Operations Project (the Project) on the groundwater regime. The objectives of the modelling were to:  review the conceptual model to identify if any new information changes the current understanding of the system;  update the existing model to include the new Project mine plan and make improvements to the model design where necessary;  verify the model performance and calibration and ensure it meets with the Australian groundwater modelling guidelines (Barnett et al., 2012);  run four model scenarios: o project mine plan (Coal Seam Gas [CSG] extraction drawdown present); o approved mine plan (CSG extraction drawdown present); o no open-cut mining (null run, which includes CSG extraction drawdown); and o no open-cut mining and no CSG extraction drawdown. and use the scenarios to assess: o project incremental impacts (Project minus Approved); o project cumulative impacts (Project minus null run); and o project and CSG cumulative impacts (Project minus null run without CSG).  predict the volumetric take of groundwater, changes in regional groundwater levels and impacts on private bore water levels due to the Project and cumulatively;  test the sensitivity of predictions to changes in model parameters; and  the rate of groundwater recovery and long term impacts occurring on cessation of mining.

E1.1 Model confidence level classification

A high level of confidence in model predictions is required for the Project. Barnett et al., (2012) developed a system to classify the confidence-level for groundwater models. Models are classified as either Class 1, Class 2 or Class 3 in order of increasing confidence. Several factors are considered in determining the model confidence-level:  available data;  calibration procedures;  consistency between calibration and predictive analysis; and  level of stresses.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 1 A Class 3 model is often referred to as an aquifer simulator, in that it encapsulates a very detailed and well understood conceptualisation. Despite the use of all available data for the model inputs, it is difficult to obtain all of the Class 3 descriptors, and an appropriate and achievable level is somewhere between an aquifer simulator and an impact model. Barnett et al., (2012) consistently suggest “it is not expected that any individual model will have all the defining characteristics of Class 1, 2 or 3 models”.

Comparison against the performance indicators for individual model classes are presented in Table E 1.1.

This shows the Continued Operations Project groundwater model is classified between a Class 2 and Class 3 model. That is, the model classification identifies:  4 out 18 (22%) performance indicators align with a Class 1 model;  12 out 22 (55%) performance indicators align with a Class 2 model; and  13 out 21 (62%) performance indicators align with a Class 3 model.

The above indicates the groundwater model has been developed to be suitable for predicting groundwater responses to changes in applied stress or hydrological conditions, and the evaluation and management of potential impacts.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 2 Table E 1.1 Model classification – model performance indicators Class Data Calibration Prediction Quantitative Indicators Not much  Not possible  Timeframe >> Calibration  Timeframe > 10x  Sparse coverage  Large error statistic  Long stress periods  Stresses < 5x 1  No metered usage  Inadequate data spread  Poor/no validation  Mass balance > 1% (or one-off 5%) (Simple) Low resolution Targets incompatible with Transient prediction but ~ Properties < > field values    Poor aquifer geometry model purpose. steady-state calibration  No review by Hydro/Modeller  Some  Partial performance  Timeframe > Calibration  Time frame = 3-10x Some long term trends  Ok coverage   Long stress periods  Stresses = 2-5x wrong. 2 ~ Some usage data/ low volumes  Short term record.  Ok validation  Mass balance <1% (Impact Baseflow estimates. Transient calibration and Some properties < > field values. Assessment)   Weak seasonal match.   Some K & S measurements prediction Review by Hydrogeologist No use of targets compatible Some high resolution topographic Some coarse discretisation in key   with model purpose (heads &  New stresses not in calibration  DEM &/or some aquifer geometry areas of grid or at key times fluxes) ~ Lots, with good coverage.  Good performance stats  Timeframe ~ calibration  Timeframe < 3x Most long term trends  Good metered usage info.   Similar stress periods  Stresses < 2x matched ~ Local climate data  Most seasonal matches ok.  Good validation  Mass balance < 0.5% 3 Calibration & prediction (Complex Kh, Kv & Sy measurements from ~  Present day data targets  consistent (transient or steady ~ Properties ∼field measurements Simulator) range of tests state). No coarse discretisation in key ~ High resolution DEM all areas. Head & Flux targets used to Similar stresses to those in  ~  areas (grid or time) constrain calibration calibration.  Good aquifer geometry.  Review by experienced Modeller

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 3 E2 Model background

The Project is proposed to extend approved open cut mining operations at the Cameby Downs Mine. The conceptual understanding of the site is summarised in Section E2.1, and discussed in detail within the main report.

Numerical groundwater models were developed and updated as part of the approvals process and to address approval conditions for the existing operations.

In order to maintain consistency with work completed for the approved operations, the most up-to-date numerical model was utilised for the Project. The evolution of numerical models for the site is detailed in Section E2.2, and Section E2.3 provides a summary of the current model design. Updates were made to the model for the purpose of the Project, which are described in Section E2.4.

E2.1 Conceptual model

Groundwater occurrence, distribution, movement and properties are influenced by the site’s geology and key system stresses. System stresses include inputs (i.e. rainfall recharge) and outputs (i.e. upward and downward leakage, interception through ground excavation and CSG bore abstraction).

Based on the current geological data, the hydrogeological conceptual understanding for the site has remained unchanged, and as such there is no physical basis to justify changes in model conceptualisation. Therefore the existing conceptual model remains valid. The changes incorporated in the current model update include:  groundwater extraction related to CSG development;  changes of mine plan;  updates of observation data;  updates of recharge data; and  updates of the modelling code.

E2.2 History of the model

E2.2.1 Initial mine approval model - 2006

In 2006, AGE completed a groundwater impact assessment for the then proposed Cameby Downs Mine (AGE, 2006). The mine was proposed to have a 31 year mine life at an annual extraction rate of approximately 1.3 million tonnes per annum (Mtpa).

A numerical model (FEFLOW) was used to simulate the impact of the mining operations on the groundwater regime. Groundwater inflow into the mining area was dependent upon the location of the active mining area and ranged from zero, where the coal seams were above the groundwater table to 0.1 ML/day at the deepest mined area of the coal seams. Groundwater drawdown at the end of mining was simulated to extend a maximum of two kilometres from the open pit.

E2.2.2 Model update 2010

In 2010, the model was updated to represent development of the Rywung deposits some 10 km to the south-east of the current Cameby Downs Mine. Coal production for the project was proposed to be significantly increased with a 25 year mine life at a variable annual extraction rate of up to 25 Mtpa run of mine (ROM) to produce 15 Mtpa to 20 Mtpa of product coal.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 4 At this time, the numerical model was changed to the MODFLOW SURFACT code from the FEFLOW code used in 2006. The objectives and inputs for the new model were consistent with that used in 2006, with the exception of the revised mine plan. The seepage rate to the pits predicted by the model increased to 3.3 ML/day (1200 ML/year) during the final years of mining. This application did not proceed and was subsequently withdrawn.

E2.2.3 Model update 2013

The model was once again updated in 2013 to simulate a 30 year mine life at a variable annual extraction rate of up to approximately 12 Mtpa ROM coal to produce 8 Mtpa of product coal. The MODFLOW SURFACT model developed in 2010 was used as the basis to represent the changes in the mine plan. The model predicted a seepage rate to the open cut pit of about 1.6 ML/day (590 ML/year) on average during the final years of mining. Once again, this application did not proceed and was subsequently withdrawn.

E2.2.4 2015 Model Re-Calibration

In accordance with EA conditions for EPML00900113 (Condition F19 and F20), AGE updated the model in 2015 with additional field data. As part of this work, the historical mine plan (2012 to 2015) was updated in the model. Active open cut mining was simulated using the SURFACT Drain package to allow water to be removed from the model domain. The dewatering levels were the floor elevations of the MA3 coal seam in the area being mined and dewatering progressed in accordance with the mine plan. The rainfall recharge to the model domain was maintained as a percentage of long term average rainfall as per the original model development and calibration. Any change to the long term average rainfall since model development will have minimal impact on the model calibration and results.

E2.3 Model design

The model grid domain was designed to be sufficiently extensive to prevent any mining drawdown/depressurisation at maximum development associated with the Project from intersecting any model boundaries. Where necessary, natural hydrogeological boundaries such as geological units and regional catchment boundaries, were adopted in the model.

The model domain was discretised into 102,400 rectangular cells per layer (307,200 cells in total), of which 82,384 cells form those within the active model area (per layer – 247,152 cells in total). The model does not include any pinched out layers and each layer extends across the entire model domain. Layer 2 thins out where it sub-crops along it north-eastern extents, beyond which it assumes same hydraulic properties as the underlying layer 3. Cell sizes range from 50 m by 50 m within the mining area and up to 500 m by 500 m outside the Project area (Figure E 2.1).

The north-west corner of the grid is located at 220,947 mE and 7,066,034 mN (MGA 1994, Zone 56), with the grid rotated clockwise 30.5 degrees to align with major geological and hydrological features. The model extent is about 35 km from northwest to southeast, and 23 km from northeast to southwest covering an area of approximately 786.6 km2. The boundaries of this model domain included those as follows:  the sub-crop of the coal seams of interest in the north and north-east;  the Burunga-Leichhardt Fault in the west; and  a south-eastern boundary parallel to the interpreted groundwater flow direction and the dip direction of the coal measures. The coal seam sub-crop was chosen as the north to northeast model boundary as it would be unlikely for groundwater depressurisation to propagate north of the area due to the overall south-southwest groundwater flow direction and the lower permeability in Layer 3 restricting downward groundwater flow into the underlying geology below the target coal seams.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 5

The hydraulic properties of the model are based on the initial parameters established for the 2006 groundwater model (Table E 2.1). These initial parameters were based on available field data, which includes site permeability tests conducted at bores on site. The parameters have been calibrated for a better fit to the available data. In addition, the range of parameters used by the Office of Groundwater Impact Assessment (OGIA) for the Underground Water Impacts Report (UWIR), were used as a reference to set the valid ranges of the model calibration.

Table E 2.1 Summary of groundwater model parameters

Model Layer name Feature / Parameter Description / Value layer

Distribution Entire model area

Top Interpolated from topographical data

Base Base of WM3 seam plus 8.4 m

Hydraulic Conductivity 9 x 10-3 m/day Overburden, (Horizontal) 1 weathered zone and interburden Hydraulic Conductivity Horizontal Hydraulic Conductivity x 0.1 (Vertical)

Specific storage 1 x 10-6 m-1

Specific yield 1 x 10-3

Recharge 0.0455 to 0.1410 mm/annum

Distribution Entire model area until subcrop

Top Base of WM3 seam plus 8.4 m

Base Base of WM3 seam

Hydraulic Conductivity Combined coal 3.79 x 10-1 m/day 2 seams KG1 to (Horizontal) WM3 Hydraulic Conductivity Horizontal Hydraulic Conductivity x 0.1 (Vertical)

Specific storage 1 x 10-5 m-1

Specific yield 2 x 10-2

Distribution Entire model area

Top Base of WM3 seam

Base Base of WM3 seam minus 50 m

Hydraulic Conductivity Strata underlying 9 x 10-4 m/day 3 coal seam (Horizontal) interval Hydraulic Conductivity Horizontal Hydraulic Conductivity x 0.1 (Vertical)

Specific storage 1 x 10-6 m-1

Specific yield 1 x 10-5

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 7 The uncertainties in the model construction are likely to relate mostly to:  lack of heterogeneity of hydraulic parameters; and  structural uncertainty / simplifications based on combining the individual coal seams.

It is acknowledged that whilst heterogeneity exists within the geological units, there is not enough data to support fully defining this in the model layers. Likewise, while faults have been mapped in the area, the nature of these faults is not known, and therefore any potential faults within the model domain have not been incorporated into the groundwater model. This allows for un-constrained propagation of the depressurisation within the coal seam layer and adjoining layers. Similarly, the simplification of the stratigraphy into broad layers also allows for more vertical connection between the model layers than would naturally exist in the geological units they represent. This simplified layering is shown in the groundwater model section in Figure E 2.2.

In relation to the Walloon Coal Measures, this comprises sequences of siltstone, mudstone, shale and sandstone lithologies in between the coal seams, with each lithological change providing opportunity for a reduction in vertical hydraulic connection and propagation of aquifer depressurisation. With the simplified model layer setup applied in this case, a change in pressure in the coal seam model layer will be instantly transferred through to the surface layer. If more model layers were assigned to represent the different lithological units, then the impact of this change may attenuate to no impact before reaching the surface layer.

While uncertainties in the model inputs are acknowledged, the necessary simplifications are considered to create conservative predictions of the impacts from groundwater depressurisation.

Cameby Downs NNE SSW Site

Overburden Combined Coal seams Underburden below WM3 seam

Figure E 2.2 Section through groundwater model showing layer design

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 8 E2.4 Model updates Compared to historical models, several updates (mostly related to mining progression) were undertaken for the current model. Details of these are provided in the following sections (Section E2.4.1 to Section E2.4.6).

E2.4.1 Model code After the 2015 model re-calibration, the model was converted from MODFLOW-SURFACT to MODFLOW-USG (Panday et al., 2013) to enable faster convergence and post processing. MODFLOW-USG is a newer version of MODFLOW that uses a ’control volume finite difference’ approach to solving the equations of groundwater flow. It is numerically more efficient than the finite- difference approach used in previous iterations of the groundwater model. E2.4.2 Timing – proposed mining run The model was run in two stages: the-lead in period from July 2010 to December 2016 (stress periods 1 to 26) and the prediction period from January 2017 to December 2090 (stress periods 27 to 322). The quarterly (3 month) stress periods were selected to allow seasonal recharge variability to be better represented in the model run. The lead-in period was used to compare the model performance with observed field data (calibration) as well as with the performance of the previous 2015 model verification.

E2.4.3 Timing – post-mining The post-mining conditions were simulated using a steady state model. The stabilised water level for each void, obtained from WRM void water level recovery (hydrological) models, was used as a boundary condition for this model.

E2.4.4 Mine drainage During the predictive run, a drain boundary condition (DRN) was used to simulate the effect of mine operations. A nominally high drain conductance of 100 m2/day was applied to the drain cells and the elevation of the base of the modelled layer was used as the drain level. The drain cells were moved within the mine footprint in line with the proposed mine plan progression, simulating water removal from the active block for that particular stress period. The drain cell progression for both approved and proposed mining plans is presented in Figure E 2.3 and Figure E 2.4 respectively.

At the completion of mining, drain cells were removed and the model simulated post-mining conditions. A series of steady state models were created to ascertain post-mining inflows. The drain package was removed for the recovery simulation, thus allowing the groundwater levels in the coal seams and the overlying strata to recover.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 9

E2.4.5 Recharge

Recharge to the groundwater system occurs through diffuse rainfall recharge across the land surface, leakage from surface water flows (i.e. perennial streams) and overland flow. These recharge mechanisms were condensed in a single package for the model using the recharge package (RCH), used by both MODFLOW-SURFACT and MODFLOW-USG.

The recharge rates were adjusted during model calibration, with the calibration ranges based on previous model rates and rates from the OGIA 2016 UWIR groundwater model.

Table E 2.2 represents the recharge for each geological unit from the original 2015 model, and the updated recharge percentage following model conversion to MODFLOW-USG. The various recharge zones are shown in Figure E 2.5.

Table E 2.2 Modelled recharge rates

Original (2006) model Recalibration (2015) Updated diffuse Unit diffuse recharge model diffuse recharge recharge (mm/year) (mm/year) (mm/year)

Regolith (surficial cover) 0.0008 0.0325 0.097

Walloon Coal Measures 0.028 – 0.11 0.0811 – 0.0823 0.141 outcrop

Walloon Coal Measures 0.008 0.0329 0.141 subcrop (south of outcrop)

Strata underlying Walloon 0.0008 0.0325 0.046 Coal Measures

Spoil 20 13 6.49

For comparison, the OGIA 2016 UWIR groundwater model technical report (OGIA, 2016b) initially used 3.6 mm/year as the pre-calibration recharge rate applied to the Walloon Coal Measures; and a recharge rate of 2.1 mm/year was used after calibration (Table 5-21 of OGIA Technical model report [2016b]). However, the report further states “that the calibrated recharge values listed in Table 5-21 are rates which are applied at the modelled ground surface. Reference to modelled water balance results (Section 5.10) confirms that in most stratigraphic units the majority of this applied recharge is subsequently rejected via modelled “drains” located at the ground surface. Modelled net recharge is therefore negligible in many cases”. Therefore the lower rates obtained via calibration for this model can be within the valid ranges of net recharge being effectively applied to the UWIR model.

Whilst OGIA did not list the net recharge rates in the 2016 groundwater model technical report (OGIA 2016b), corresponding values were provided in Table 17 the OGIA 2012 UWIR report (GHD, 2012). This shows the calibrated recharge rate of 2.1 mm/year for the 2012 OGIA model (which is the same value calibrated in the 2016 OGIA model) reduced to a net recharge rate of 1.0 mm/year for the productive coal layer, and from 0.0 mm/year to 0.2 mm/year for the upper and lower aquitards. Since the upper aquitard and shallow productive coal seams have been lumped into one layer in the updated 2017 model, the calibrated recharge rate for the Walloon Coal Measures (0.141 mm/year) is considered appropriate and aligns with the OGIA UWIR groundwater model. Similarly, the updated 2017 model calibrated recharge rate for the cover layer that groups the Springbok Sandstone and intervening aquitards (0.097 mm/year), compares favourably with the net recharge for these units in the OGIA 2016 UWIR, which varies from 0.0 mm/year to 0.6 mm/year (Table 17 in GHD, 2012).

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 12

E2.4.6 Boundary conditions

As discussed in Section E2.3, the model domain is partly bound by geological faults; therefore “no flow” boundaries are specified for three sides of the numerical groundwater model, as per the original model design. While the eastern border is parallel to groundwater flow and 6 km from the mine area, the western border was positioned at the Burunga-Leichhardt Fault, which is assumed to be a barrier to the groundwater flow. The north/north-east border is formed by the subcrop of the nearly impermeable strata underlying the coal seam interval.

The south/south-west model border, which represents the down-dip boundary of the model domain, is designated as an outflow boundary. This area was previously simulated as a fixed hydraulic head boundary condition (282 mAHD). In order to account for the impacts caused by existing CSG operations across the region, drawdowns extracted from the UWIR 2016 model were applied to the fixed head boundary, and a general head boundary (GHB) condition was assigned across the entirety of the model domain.

The use of GHB to represent CSG impacts was selected as the model is not designed for dual porosity flow. CSG impacts were already captured within the UWIR 2016 groundwater model developed by OGIA. AGE liaised with OGIA and obtained predicted groundwater drawdown levels for the stratigraphy relevant to the Project in February 2017. The reason for using the drawdown data modelled by OGIA in the current groundwater model was to ensure the Project represents cumulative impacts consistently with the best available predictions.

E2.4.7 Water budget

Table E 2.3 shows the average rates of water transfer (flow into and out of the model) over the period of the historic transient model (2010 to 2016). Table E 2.4 shows the average flow rates across model boundaries for the prediction period of 2017 to 2090.

Table E 2.3 Model budgets – transient historic

Average water transfer - 2010 – 2016 (ML/day) Parameter Input Output

Rainfall recharge 0.25 -- Drains -- 0.22 General head boundary 0.12 0.07 Constant head boundary 0.42 1.10

Table E 2.4 Model budgets – transient prediction

Average water transfer - 2017 – 2090 (ML/day) Parameter Input Output

Rainfall recharge 0.21 -- Drains -- 0.51 General head boundary 1.26 0.62 Constant head boundary 1.22 1.92

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 14 It should be noted that the above budgets will not balance as during the transient periods they represent there has been drawdown depressurisation of the groundwater system, hence a change (loss) in storage.

Groundwater recharge during the lead-in (historical) period is on average 0.25 ML/day. Mining during this period is quite shallow and partially above the groundwater table, simulated via the DRN package with an average extraction rate of 0.24 ML/day. As mining operations progress to the deeper coal seams, the average rate increases to 0.73 ML/day (see Table E 2.4).

The mass balance error is a parameter used to quantify the quality of the internal numerical solution of the simulation, defined as the difference between the model inflows and outflows at the completion of calibration model run. The mass balance of the transient simulation was generally less than 0.5% indicating that the model was numerically stable and achieved an accurate numerical solution.

E3 Model calibration and verification The groundwater model calibration was verified for the historic transient run (2010 to 2016) using available groundwater level data. The model was calibrated by adjusting hydraulic conductivity, recharge and boundary conditions (GHB conductance) parameters to produce the best match between the observed and simulated water levels. The modelled hydrographs were compared to observed water levels as well as to previously modelled heads (2015 re-calibration). The 2015 model predictions were used to verify that current updates to the model did not fundamentally change the model prediction capability.

E3.1 Calibration heads The transient model simulated water levels in all available bores at the site, which includes the site monitoring bores (CD018, CD034C, CD036R, CD037C, CD056 and CD065) and water levels measured in some of the mine exploration boreholes. The monitoring bores are all located within the footprint of the proposed mine and will be eventually destroyed as the mining progresses. Additional groundwater level data was sourced from CSG monitoring bores and registered bores data from the Department of Natural Resources and Mines (DNRM) groundwater database that are located within the model domain. This is from data that is available in the public domain.

Figure E 3.1 presents the observed and simulated groundwater levels graphically as a scattergram. The calibration hydrographs for the site monitoring bores and regional registered bores are shown in Appendix E1, which present the calibration data in context with the overall predicted drawdown for each bore. These show that overall the drawdown responses are generally well represented by the simulated water level drawdowns. Where the simulated drawdowns do not exactly match the observed drawdown responses, this are considered to be due to:

 the groundwater model simulating the mine progression in 5 year blocks which does not allow for small changes or variation in the mine plan to be properly represented;  representing the fractured rock flow by an equivalent porous media approach, when in reality there would be heterogeneity from faults and fractures that would either amplify or restrict groundwater movement in certain directions; and  the homogeneous application of hydraulic parameters in the groundwater model that are likely heterogeneous in distribution in the real world.. Hence, it is accepted and acknowledged that whilst there are differences in the magnitude and timing of simulated drawdown responses to those observed, these are to be expected given the overall simplification and assumptions incorporated in the groundwater model. The variation in simulated versus observed groundwater trends are therefore considered acceptable for the purposes of this groundwater model.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 15

Figure E 3.1 Transient calibration – modelled vs observed groundwater levels

The root mean square (RMS) error calculated for the calibrated model was 4.43 m. The total measured head change across the model domain was 49.7 m, with a standardised RMS (SRMS) of 8.9%. A lower SMRS would most likely be achieved through inclusion of heterogeneity to the aquifer parameters (as well as depth dependence). However, the number and distribution of currently available observations would not support a calibrated parameter set that would also limit parameter non-uniqueness. That is, whilst it may be possible to find a set of parameter values that were able to match the observations almost perfectly, the required heterogeneity this creates would remove the model’s predictive potential due to parameter non-uniqueness. The other critical aspect of the calibration is that all of the observation data is close to the mine and appears to have responded to historical mining. Incorporation of the historical mine progression has required it to be simplified to allow it to fit in with the model discretisation and transient progression, which in turn has impacted on the ability of the model to perfectly match the water level responses.

All the hydrographs (except CD056) contain simulated and observed data (field measurements). The calibration hydrographs for the site monitoring bores are shown in Appendix D1, which presents the calibration data in context with the overall predicted drawdown for each monitoring bore. A manual calibration was undertaken to fit the simulation to observed data. The manual process was preferred over an automatic calibration given the relatively limited data available and the better judgement provided by the groundwater modeller’s experience, which can better assess observation trends and the overall behaviour of the system. The Australian Modelling Guidelines (Barnett et al, 2012) suggest a SRMS of 10% or lower constitute a reasonably well calibrated model. This model meets this criterion. Additionally, a reasonably good match between the predicted and observed groundwater levels and trends, which suggest the model calibration is adequate. More widespread observation data around the model domain which could support the simulation of non-homogeneous hydraulic parameters would be necessary for an upgrade of the simulation and an improved prediction capacity.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 16 E4 Sensitivity analysis

The sensitivity analysis was extended from the standard assessment on the calibration to explore the potential uncertainty in the model predictions. Selected model parameters were varied up and down by half an order of magnitude for this purpose; this provides a significant enough change to determine a relative sensitivity without significantly un-calibrating the model and producing an unrealistic response.

The following model inputs were varied as part of the sensitivity analysis:  ±0.5 order of magnitude change in horizontal and vertical hydraulic conductivity (K) in the Walloon Coal Measures (Layer 2);  ±0.5 order of magnitude change in specific yield and specific storage (S) in the Walloon Coal Measures (Layer 2); and  ±0.5 order of magnitude change in the rainfall recharge rate across the model domain.

These changes represent the expected bounds of the groundwater regime. The following sections present the results of these sensitivity analyses in terms of their influence on the inflow predictions, drawdown and groundwater users.

E4.1 Sensitivity of predicted inflows

The predicted seepage rates resulting from the sensitivity model simulations are shown on:  Figure E 4.1 for changed hydraulic conductivity in the Walloon Coal Measures;  Figure E 4.2 for changed specific storage and specific yield in the Walloon Coal Measures; and  Figure E 4.3 for changed recharge across the model domain.

Figure E 4.1 Sensitivity of coal seam hydraulic conductivity to predicted inflows

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 17

Figure E 4.2 Sensitivity of coal seam specific storage and specific yield to predicted inflows

Figure E 4.3 Sensitivity of recharge to predicted inflows

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 18 The sensitivity analysis results show that the predicted groundwater seepage rates are most sensitive to changes in the recharge and storage values adopted for the Walloon Coal Measures. In particular, the sensitivity to specific yield would be a function of the change from confined to unconfined storage conditions within the coal seams adjacent to the working pit.

Typically, when undertaking sensitivity analyses, the expected behaviour of the model is to uniformly raise or lower inflows depending on the parameter tested. This was the case when assessing the recharge rate and aquifer storage values (i.e. higher recharge rate and storage values produced higher inflows and vice versa, lower recharge rate and storage values produced lower inflows). However, when assessing the model sensitivity to hydraulic conductivity the behaviour of the predicted mine inflow is more complex. When increasing the model hydraulic conductivity value, the modelled steady state heads lower, resulting in a larger portion of the model becoming unsaturated around the coal seam subcrop area, and reducing inflow to the pit during the early stages of mining. However, as mining progresses and moves into saturated areas, the effect of a more conductive aquifer takes over resulting in higher inflows as expected.

The opposite occurs for the sensitivity analysis for a lower hydraulic conductivity simulation. In this instance, there is a larger area of saturation compared to the calibrated model. This results in higher inflows at the beginning of the simulation, due to higher water levels in steady state, and a more generous extent of saturated aquifer available surrounding of the mine.

The potential range of peak inflow rates is presented in Table E 4.1.

Table E 4.1 Summary results of sensitivity analysis Parameter Maximum mine Parameter change seepage (ML/day) Calibrated seepage no change 0.96 (baseline)

Horizontal and vertical × (10+0.5) 1.02 hydraulic conductivity (Kh, Kv) × (10-0.5) 0.80

Specific yield and × (10+0.5) 1.73 specific storage (Sy, Ss) × (10-0.5) 0.74

× (10+0.5) 2.53 Recharge × (10-0.5) 0.56

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 19 E4.2 Sensitivity of predicted drawdown

The predicted zones of depressurisation (represented by the 1 m drawdown contour) for each of the sensitivity model simulations, are shown on Figure E 4.4. The presented drawdowns are for model Layer 2 representing the Walloon Coal Measures.

The biggest change in drawdown impact was driven by change in recharge, where the 1 m drawdown contour shifts approximately 2 km to 3 km outwards, and 1 km inwards, in line with either increasing or decreasing the recharge rate by half an order of magnitude.

Figure E 4.4 demonstrates the issue discussed above concerning the counterintuitive and complex results from changes to hydraulic conductivity. In particular, the predicted 1 m drawdown contours for the hydraulic conductivity values can be seen crossing over each other (and the baseline contour), and this is driven by the level of saturation in the north-eastern portion of the mine footprint. While a higher hydraulic conductivity would intuitively result in a larger drawdown extent, the higher hydraulic conductivity also means the water levels within the pit are lower at the start of simulation, resulting in a larger portion of the northeast mine footprint being predicted to be unsaturated. For the decreased hydraulic conductivity simulation the opposite is the case. In this instance, a larger portion of the mine footprint is predicted to be saturated, causing the 1 m drawdown contour to plot further north and crossing over the baseline and corresponding increased hydraulic conductivity contours.

E4.3 Sensitivity of impacts on groundwater users

As discussed in Section 9.4.5 of the Groundwater Assessment report, the baseline drawdown impact area (represented by 1m drawdown contour) does not intersect any registered groundwater uses. Similarly, the sensitivity analysis results in no additional registered groundwater supply bores being potentially impacted by the adopted change in model parameters.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 20

E5 References

Barnett, B, Townley, LR, Post, V, Evans, RE, Hunt, RJ, Peeters, L Richardson, S, Werner, AD, Knapton, A, & Boronkay, A (2012), “Australian groundwater modelling guidelines”, Waterlines report, National Water Commission, Canberra.

GHD (2012), ‘Report for QWC17-10 Stage 2, Surat Cumulative Management Area Groundwater Model Report’, prepared for Queensland Water Commission, May 2012.

OGIA (2016b), ‘Groundwater modelling report for the Surat Cumulative Management Area’, compiled by the Office of Groundwater Impact Assessment, Department of Natural Resources, September 2016.

Panday, S, Langevin, CD, Niswonger, RG, Ibaraki, M & Hughes, JD (2013), “MODFLOW-USG version 1: An unstructured grid version of MODFLOW for simulating groundwater flow and tightly coupled processes using a control volume finite-difference formulation”; U.S. Geological Survey Techniques and Methods, book 6, chap. A45, 66 p.

Australasian Groundwater and Environmental Consultants Pty Ltd Groundwater Impact Assessment – Cameby Downs (G1831) | Appendix E | 22

Appendix E1 Simulated and observed hydrographs

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