Heritage Minerals has a unique approach to solving the economic barriers to treating low-grade tailings. A combination of the worlds best technology and many years of operational experience can turn around projects that are otherwise not feasible. Heritage Minerals designs and implements innovative solutions for technically tricky projects. They are also a environmentally and socially responsible problem solver.
Mount Morgan Mine - Upper Mundic Gully TSF Environmental Authority Amendment October 2025
PREPARED BY: WULGURU TECHNICAL SERVICES DOCUMENT ID: 2025.06005 VERSION: 2.0 DATE OF SUBMISSION: 23/10/2025 PREPARED FOR: Heritage Minerals Pty Ltd
Contact Details
Company
Wulguru Technical Services Pty Ltd
Project Manager
Lachlan McQuire
lachlan@wulgurutechservices.com.au
PO Box 2553 IDALIA QLD 4810
ABN
79 644 301 655
Disclaimer
This report has been prepared by Wulguru Technical Services Pty Ltd for and on behalf of Wulguru
Technical Services Pty Ltd’s Client and is subject to and issued in connection with the agreement
between Wulguru Technical Services Pty Ltd.
Wulguru Technical Services Pty Ltd cannot be held liable for third party reliance on this document. This
report is based on information available to Wulguru Technical Services Pty Ltd and could be different if
the information on which this report is based upon is inaccurate or incomplete.
Whilst all reasonable effort has been made to ensure that the contents of this publication are factually
correct, Wulguru Technical Services Pty Ltd does not accept responsibility for the accuracy or
completeness of the contents and 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 this publication.
This report may utilise the results of work carried out by others. These results have been used in good
faith by Wulguru Technical Services Pty Ltd and Wulguru Technical Services Pty Ltd cannot be held
responsible for their accuracy.
Document Control and History
Version
Date
Description
Prepared By
Reviewed By
V1.0
8/07/2025
For DETSI prelodgement
LM
LM
V2.0
28/10/2025
For DETSI review
LM
LM
Citation
Wulguru Technical Services 2025, Environmental Authority Amendment, Upper Mundic Gully TSF,
Mount Morgan Mine Prepared by Wulguru Technical Services Pty Ltd for Heritage Minerals Pty Ltd.
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Wulguru Technical Services Pty Ltd – Supporting Information Report
Executive Summary
Wulguru Technical Services (WTS) was engaged by Heritage Minerals Pty Ltd (Heritage Minerals), the
owners and operators of Mount Morgan Mine, to prepare supporting information for an amendment to
Environmental Authority (EA) EPML00433013.
The purpose of this document is to describe existing environmental values and assess potential
environmental impacts that may arise from the proposed amendments. The proposed amendments
relate to:
• Authorise Upper Mundic Gully Tailings Storage Facility (TSF) by inclusion as a mine feature
in the EA;
• Update Table A1, and associated Schedule I Figure 1, to address to be determined (TBDs)
associated with the pipe corridor and exploration mine features; and
• Fix minor erroneous issues in the EA that impact on the processed tailings volumes for
discharge into Sandstone Gully TSF.
The Heritage Minerals Project will ultimately result in improved environmental outcomes at the Mount
Morgan Mine through the excavation and treatment of historical Acid Rock Drainage (ARD) generating
mine waste and redeposition of processed tailings into the Sandstone Gully TSF, Open Cut Pit (OCP)
and the Upper Mundic Gully TSF (if approved). This will result in the removal of the source of ARD
generating material from across the site reducing recharge of and seepage from mine waste structures.
This will reduce impacts from the Mount Morgan Mine to the receiving environment including the Dee
River in accordance with the State’s Rehabilitation Plan (Unger et al, 2003) and Phase 2 Agreement.
The Upper Mundic Gully TSF approval will provide a more resilient tailings/water management strategy
that can better accommodate more extreme climatic conditions and further reduce water balance risks.
Approval and operation of the Upper Mundic Gully TSF will provide further comfort to key project
stakeholders including the Independent Technical Expert (ITE) and the Department of Natural
Resources and Mines, Manufacturing and Regional and Rural Development (DNRMMRRD) by
reducing the likelihood of overtopping events from structures potentially impacting offsite environmental
values and reducing operational pressures on the Water Treatment Plant (operated by the
DNRMMRRD) that adjoins the OCP.
The Upper Mundic Gully TSF footprint is highly modified and surrounded by previous authorised mining
disturbances that have reduced environmental values. Potential impacts to environmental values from
the construction and operation of Upper Mundic Gully TSF have been fully identified. Mitigation and
management measures for reducing environmental harm for unavoidable impact to some
environmental values have been proposed.
The proposed amendment has been determined to be of negligible risk to all environmental values.
Existing controls can continue to be implemented to maintain the level of risk to as low as reasonably
possible.
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Wulguru Technical Services Pty Ltd – Supporting Information Report
Contents
1. Introduction................................................................................................................................ 14
1.1. Purpose ..................................................................................................................................... 14
1.2. Project Location ........................................................................................................................ 15
1.3. Environmental Authority Holder ................................................................................................ 17
1.4. Environmentally Relevant Activities .......................................................................................... 17
1.5. Mining Tenements ..................................................................................................................... 17
1.6. Real Property Descriptions ....................................................................................................... 20
2. Overview of Proposed EA Amendments................................................................................... 25
2.1. Proposed Amendments............................................................................................................. 25
2.1.1. Proposed Amendment 1: Authorise Upper Mundic Gully TSF ................................................. 25
2.1.2. Proposed Amendment 2: Update Table A1 and Figure 1 to address TBDs and reduce
duplication ............................................................................................................................................. 28
2.1.3. Proposed Amendment 3: Fix Minor Erroneous Issues in the EA.............................................. 28
2.2. Amendment Justifications ......................................................................................................... 32
2.2.1. Justification for Proposed Amendment 1 .................................................................................. 32
2.2.2. Justification for Proposed Amendment 2 .................................................................................. 33
2.2.3. Justification for Proposed Amendment 3 .................................................................................. 34
2.3. Proposed Conditioning .............................................................................................................. 34
2.3.1. Conditions within the EA ........................................................................................................... 34
2.3.2. Tables within the EA ................................................................................................................. 38
2.3.3. Figures within the EA ................................................................................................................ 44
2.4. Summary of Risks and Likely Magnitude of Impacts on Environmental Values .......................46
2.5. Assessment Level Decision ...................................................................................................... 51
2.5.1. Previous Site Disturbance ......................................................................................................... 52
2.6. Content of Supporting Information ............................................................................................ 55
3. Overall Project Description........................................................................................................ 57
3.1. Overall Project History .............................................................................................................. 57
3.1.1. Handover to the State ............................................................................................................... 58
3.1.2. Abandoned Mine Status ............................................................................................................ 58
3.1.3. Past Reprocessing Endeavours................................................................................................ 59
3.1.4. Phase 2 Agreement .................................................................................................................. 60
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Wulguru Technical Services Pty Ltd – Supporting Information Report
3.2. Alternatives to the Amendments ............................................................................................... 62
3.2.1. Amendment #1 .......................................................................................................................... 62
3.2.2. Amendment #2 .......................................................................................................................... 63
3.2.3. Amendment #3 .......................................................................................................................... 63
3.3. Standard Criteria Assessment .................................................................................................. 63
4. Upper Mundic Gully TSF Description........................................................................................ 66
4.1. Upper Mundic Gully Location and Catchment Description ....................................................... 66
4.2. Topography and Drainage ........................................................................................................ 71
4.3. Proposed TSF ........................................................................................................................... 76
4.3.1. Basis of Design ......................................................................................................................... 81
4.3.2. Dam Break and Consequence Category Assessment ............................................................. 82
4.3.2.1. Failure mechanisms ................................................................................................................. 83
4.3.2.2. Consequence Category Assessment ....................................................................................... 83
4.3.2.2.1.
ANCOLD Guidelines ......................................................................................................... 83
4.3.2.2.2.
DETSI Guidelines .............................................................................................................. 84
4.3.2.2.3.
Dam Break Consequence Results .................................................................................... 84
4.3.2.2.4.
Consequence Classification ANCOLD.............................................................................. 85
4.3.2.2.5.
Consequence Classification DETSI .................................................................................. 85
4.3.2.2.6.
Environmental Spill/Failure to contain (Overtopping Consequence) ................................ 86
4.3.2.2.7.
Environmental Spill/Failure to contain (Overtopping Consequence) - ANCOLD..............87
4.3.2.2.8.
Environmental Spill/Failure to contain (Overtopping Consequence) – DETSI .................87
4.3.2.2.9.
Failure to contain (Seepage) – Consequence .................................................................. 88
4.3.3. Tailings and Water Management .............................................................................................. 89
4.3.4. Water Balance ........................................................................................................................... 89
4.3.5. Deposition Volumes .................................................................................................................. 94
4.3.6. Decant Pond.............................................................................................................................. 96
4.3.7. Seepage and Tunnel Management........................................................................................... 96
4.3.8. Flood Potential .......................................................................................................................... 97
4.3.9. Clean Water Diversion ............................................................................................................ 100
4.3.10. Potential impacts of future deposition expansion.................................................................... 100
4.3.11. Process Plant Flow Sheet ....................................................................................................... 101
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Wulguru Technical Services Pty Ltd – Supporting Information Report
4.3.12. Tailings Geochemical Characterisation .................................................................................. 103
5. Environmental Setting and Considerations ............................................................................. 106
5.1. Climate .................................................................................................................................... 106
5.2. Geology ................................................................................................................................... 108
5.3. Soils......................................................................................................................................... 109
5.4. Bioregion and subregion ......................................................................................................... 110
5.4.1. Land Zones ............................................................................................................................. 111
5.5. Hydrology ................................................................................................................................ 111
5.6. Site Hydrogeology ................................................................................................................... 113
5.6.1. Groundwater Quality ............................................................................................................... 116
5.6.2. Conceptual Site Model ............................................................................................................ 116
5.6.3. Groundwater Recharge and Discharge .................................................................................. 125
5.6.4. Groundwater Modelling ........................................................................................................... 127
5.7. Ecology.................................................................................................................................... 127
5.7.1. Desktop Assessment .............................................................................................................. 127
5.7.2. Regional Ecosystems Field Verified ....................................................................................... 129
5.7.3. Ecological Surveys .................................................................................................................. 130
5.7.3.1. Conservation significant flora ................................................................................................. 131
5.7.3.2. Introduced Flora Species ....................................................................................................... 135
5.7.4. Likelihood of Occurrence Analysis .......................................................................................... 136
6. Potential Environmental Impacts and Management ............................................................... 138
6.1. Existing Management Practices.............................................................................................. 138
6.2. Surface Water and Wetlands .................................................................................................. 139
6.2.1. Values ..................................................................................................................................... 140
6.2.2. Impact Assessment ................................................................................................................. 142
6.2.2.1. Acid Sulfate Soils ................................................................................................................... 143
6.2.2.2. Acid Producing Rock .............................................................................................................. 143
6.2.3. Management Practices ........................................................................................................... 143
6.3. Groundwater............................................................................................................................ 144
6.3.1. Values ..................................................................................................................................... 144
6.3.2. Impact Assessment ................................................................................................................. 145
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Wulguru Technical Services Pty Ltd – Supporting Information Report
6.3.3. Management Practices ........................................................................................................... 146
6.3.3.1. Groundwater Monitoring ......................................................................................................... 146
6.4. Land ........................................................................................................................................ 148
6.4.1. Values ..................................................................................................................................... 148
6.4.2. Rehabilitation........................................................................................................................... 149
6.4.2.1. Appropriate Land Use ............................................................................................................ 149
6.4.2.1.1.
Land Use Suitability ........................................................................................................ 150
6.4.2.1.2.
Land Use Strategies and Regional Planning .................................................................. 150
6.4.2.1.3.
Historic and Surrounding Land Uses .............................................................................. 152
6.4.2.1.4.
Description of Nominated PMLU ..................................................................................... 152
6.4.2.2. Rehabilitation Methodology .................................................................................................... 152
6.4.2.3. Cover Systems ....................................................................................................................... 153
6.4.2.4. Revegetation .......................................................................................................................... 154
6.4.3. Impact Assessment ................................................................................................................. 155
6.4.4. Management Practices ........................................................................................................... 155
6.5. Noise and Vibration ................................................................................................................. 155
6.5.1. Values ..................................................................................................................................... 156
6.5.2. Impact assessment ................................................................................................................. 157
6.5.3. Management Practices ........................................................................................................... 157
6.6. Air Quality ................................................................................................................................ 158
6.6.1. Values ..................................................................................................................................... 158
6.6.2. Impact Assessment ................................................................................................................. 159
6.6.3. Management Practices ........................................................................................................... 159
6.7. Social and Community ............................................................................................................ 160
6.7.1. Values ..................................................................................................................................... 160
6.7.2. Impact Assessment ................................................................................................................. 160
6.7.3. Management Practices ........................................................................................................... 161
6.8. Cultural Heritage ..................................................................................................................... 161
6.8.1. Indigenous Heritage ................................................................................................................ 161
6.8.1.1. Values..................................................................................................................................... 161
6.8.1.2. Impact Assessment ................................................................................................................ 161
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Wulguru Technical Services Pty Ltd – Supporting Information Report
6.8.1.3. Management Practices........................................................................................................... 162
6.8.2. Non-Indigenous Heritage ........................................................................................................ 162
6.8.2.1. Values..................................................................................................................................... 162
6.8.2.2. Impact Assessment ................................................................................................................ 163
6.8.2.3. Management Practices........................................................................................................... 163
6.9. Nature Conservation ............................................................................................................... 163
6.9.1. Significant Residual Impact Assessment ................................................................................ 163
6.9.1.1. Cycas megacarpa .................................................................................................................. 164
6.9.1.2. Koala (Phascolarctos cinereus) ............................................................................................. 168
6.9.1.3. Ghost bat (Macroderma gigas) .............................................................................................. 170
6.9.1.4. Greater glider (southern and central) (Petauroides volans) ................................................... 173
6.9.1.5. Yellow-bellied glider (south-eastern) (Petaurus australis australis) ....................................... 176
6.9.1.6. White-throated needletail (Hirundapus caudacutus) .............................................................. 178
6.9.1.7. Grevillea hockingsii ................................................................................................................ 181
6.9.1.8. Short-beaked echidna (Tachyglossus aculeatus) .................................................................. 184
6.9.1.9. Regulated Vegetation – Category B ‘Of Concern’ Regional Ecosystem ............................... 185
6.10. Waste Management ................................................................................................................ 187
6.10.1. Values ..................................................................................................................................... 187
6.10.2. Impact Assessment ................................................................................................................. 188
6.10.3. Management Practices ........................................................................................................... 188
6.11. Greenhouse Gas Assessment ................................................................................................ 189
6.11.1. Values ..................................................................................................................................... 190
6.11.2. Impact Assessment ................................................................................................................. 191
6.11.3. Management Practices ........................................................................................................... 194
7. Environmental Risk Assessment............................................................................................. 196
7.1. Overview ................................................................................................................................. 196
7.2. Risk Identification .................................................................................................................... 197
7.3. Risk Analysis and Evaluation .................................................................................................. 198
7.4. Risk Assessment Results........................................................................................................ 200
8. Bibliography............................................................................................................................. 209
9. Abbreviations........................................................................................................................... 212
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Wulguru Technical Services Pty Ltd – Supporting Information Report
10. Appendix A: 2019 Plan of Operations ..................................................................................... 214
11. Appendix B: Sandstone Gully TSF Report.............................................................................. 215
12. Appendix C: WSP Wattle Gully TSF CCA .............................................................................. 216
13. Appendix D: WSP Wattle Gully TSF Design Report ............................................................... 217
14. Appendix E: Factual Ecological Assessment Report for Upper Mundic Gully ........................ 218
15. Appendix F: Waste Management Plan ................................................................................... 219
16. Appendix G: Hydrobiology Report........................................................................................... 220
17. Appendix H: Water Balance .................................................................................................... 221
18. Appendix I: Groundwater Data Review ................................................................................... 222
19. Appendix J: Cycas megacarpa Management Plan ................................................................. 223
20. Appendix K: Grevillea hockingsii Management Plan .............................................................. 224
21. Appendix L: GHG Assessment ............................................................................................... 225
22. Appendix M: WTS Ecological Reports .................................................................................... 226
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Wulguru Technical Services Pty Ltd – Supporting Information Report
List of Tables
Table 1. Environmental Authority Holder .............................................................................................. 17
Table 2. Current Authorised ERAs and Resource Activities ................................................................. 17
Table 3. Mining Tenements................................................................................................................... 18
Table 4. Underlying landholders on the relevant Mining Lease ............................................................ 20
Table 5. Proposed Modifications and new conditions within the EA .................................................... 34
Table 6. Proposed Table A1 – Authorised mining activities and locations Replacement..................... 38
Table 7. Proposed Table F1 Replacement ........................................................................................... 40
Table 8. Proposed Table F2 Replacement ........................................................................................... 42
Table 9. Proposed Table H1 Replacement ........................................................................................... 43
Table 10. Proposed Table H2 Replacement ......................................................................................... 44
Table 11. Proposed Table H3 Replacement ......................................................................................... 44
Table 12. Environmental Values Risk Assessment Summary .............................................................. 47
Table 13. Minor amendment criteria ..................................................................................................... 51
Table 14. Table of Requirements.......................................................................................................... 55
Table 15. Processed Tailings Disposal Options Assessment............................................................... 62
Table 16. Standard Criteria Assessment .............................................................................................. 64
Table 17. Design Criteria and basis of design ...................................................................................... 81
Table 18. Summary of results for consequence category assessment ................................................ 82
Table 19. Summary of Failure Mechanisms Assessed......................................................................... 83
Table 20. PAR estimates (ANCOLD) .................................................................................................... 85
Table 21. PAR Estimates (DETSI) ........................................................................................................ 85
Table 22. Consequence Category Assessment for Upper Mundic Gully TSF...................................... 85
Table 23. Consequence Category Assessment for Upper Mundic Gully TSF – DETSI (Dam Break
scenario)................................................................................................................................................ 85
Table 24. Consequence Category Assessment for Upper Mundic Gully TSF – ANCOLD (Environmental
Spill) ...................................................................................................................................................... 87
Table 25. Consequence Category Assessment for Upper Mundic Gully TSF – ANCOLD (Environmental
Spill) ...................................................................................................................................................... 87
Table 26. Consequence Category Assessment for Upper Mundic Gully TSF – ANCOLD (Environmental
Spill) ...................................................................................................................................................... 88
Table 27. Simulated dates for OCP levels at various RLs .................................................................... 90
Table 28. Estimated Tailings Storage ................................................................................................... 94
Table 29. Tailings properties compared to Relevant Guidelines ........................................................ 105
Table 30. Mean Maximum and Minimum Temperature for the Rockhampton Airport (BOM) ............106
Table 31. Soil Type Summary............................................................................................................. 109
Table 32. Land Zones and associated geologies occurring in the project area ................................. 111
Table 33. Conceptual Source Pathway Receptors Current Conditions .............................................. 119
Table 34. Conceptual Source Pathway Receptors Post Mining ......................................................... 120
Table 35. Simulated Groundwater Flows by Sub-Catchment............................................................. 121
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Wulguru Technical Services Pty Ltd – Supporting Information Report
Table 36. Potential Scenarios for Groundwater/ Seepage Flows ....................................................... 122
Table 37. Desktop assessment information sources .......................................................................... 128
Table 38. Descriptions for Regional Ecosystems Ground-truthed within the Project area as per RE
Description Database (Queensland Herbarium, 2023) ....................................................................... 129
Table 39. Ecological Surveys.............................................................................................................. 130
Table 40. Restricted matters and WoNs occurring in the project area ............................................... 135
Table 41. Summary of likelihood of occurrence of MSES .................................................................. 136
Table 42. Project Stakeholders ........................................................................................................... 160
Table 43. Summary of SRI assessment results.................................................................................. 164
Table 44. SRI assessment - Cycas megacarpa ................................................................................. 166
Table 45. SRI assessment - Koala ( Phascolarctos cinereus )............................................................. 169
Table 46. SRI assessment - ghost bat ( Macroderma gigas ) .............................................................. 172
Table 47. SRI assessment - greater glider ( Petauroides volans ) ....................................................... 174
Table 48. SRI assessment - yellow-bellied glider ( Petaurus australis australis ) ................................ 176
Table 49. SRI assessment - white-throated needletail ( Hirundapus caudacutus ) .............................. 180
Table 50. SRI assessment - Grevillea hockingsii ............................................................................... 182
Table 51. SRI assessment - short-beaked echidna ( Tachyglossus aculeatus ) .................................. 184
Table 52. SRI assessment - regulated vegetation – Category B........................................................ 185
Table 53. DETSI Requirement ............................................................................................................ 189
Table 54. GHG Emission Inventory .................................................................................................... 191
Table 55. Estimated Scope 1 and 2 Emissions .................................................................................. 193
Table 56. Management Practices to mitigate emissions .................................................................... 194
Table 57. Likelihood of Exposure of Hazard ....................................................................................... 198
Table 58. Consequence Classification................................................................................................ 199
Table 59. Risk Level Classification Matrix .......................................................................................... 199
Table 60. Risk Assessment Results ................................................................................................... 201
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Wulguru Technical Services Pty Ltd – Supporting Information Report
List of Figures
Figure 1. Site Locality............................................................................................................................ 16
Figure 2. Mining Leases ........................................................................................................................ 19
Figure 3. Underlying Lots within Mining Lease ..................................................................................... 24
Figure 4. Upper Mundic Gully TSF extent............................................................................................. 27
Figure 5. Sandstone Gully TSF Storage Capacity (Golder, 2020)........................................................ 29
Figure 6. Pipe Corridor Extent .............................................................................................................. 29
Figure 7. Extract from 2019 PoO (Source AARC, 2019) ...................................................................... 30
Figure 8. Extract from PoO 2017 (AARC) ............................................................................................. 31
Figure 9. Replacement Schedule I, Figure 1 in the EA......................................................................... 45
Figure 10. Areas Historically Disturbed by Mining ................................................................................ 54
Figure 11. Waste Rock Disposal in Upper Mundic Gully from West to East (photograph taken 1942) 67
Figure 12. Waste Rock Disposal in Upper Mundic Gully Plan View (photograph taken 1953) ............67
Figure 13. Western Dump within Upper Mundic Gully from the south looking north ............................ 68
Figure 14. Western Dump within Upper Mundic viewed from the base looking east ........................... 69
Figure 15. Waste Rock Disposal in Upper Mundic Gully (GHD)........................................................... 70
Figure 16. Mount Morgan Drainage Network Current........................................................................... 72
Figure 17. Mount Morgan Drainage Network Pre-Mining ..................................................................... 73
Figure 18. Sub Catchments occurring across Mount Morgan Mine...................................................... 74
Figure 19. Topography within Mount Morgan Mining Leases (QLD Globe) ......................................... 75
Figure 20. General Arrangement Plan .................................................................................................. 77
Figure 21. Plan and Longitudinal Section Stage 1................................................................................ 78
Figure 22. Plan and Longitudinal Section Stage 2................................................................................ 79
Figure 23. Typical Embankment Section .............................................................................................. 80
Figure 24. Upper Mundic Gully simulated forecast water levels for all phases .................................... 91
Figure 25. OCP simulated forecast water levels for all phases ............................................................ 91
Figure 26. Simulated mean forecast water balance ............................................................................. 93
Figure 27. Stage 1 Tailings Beach Surface .......................................................................................... 94
Figure 28. Stage 1 Stage-Storage Curve.............................................................................................. 95
Figure 29. Stage 2 Tailings Beach Surface .......................................................................................... 95
Figure 30. Stage 2 Stage-Storage Curve.............................................................................................. 96
Figure 31. Proposed Tunnel Portal Plug Design Section ..................................................................... 97
Figure 32. Overtopping and piping failure configurations (US Army Corps of engineers, 2014)..........98
Figure 33. Stage 1 Sunny Day Failure Maximum Depth (m) ................................................................ 99
Figure 34. Stage 2 Sunny Day Failure Maximum Depth (m) ................................................................ 99
Figure 35. Potential interaction of the Upper Mundic Gully TSF failure discharges with the proposed
Sandstone Gully TSF embankment .................................................................................................... 101
Figure 36. Process Plant Flow Diagram ............................................................................................. 102
Figure 37. Mean maximum and minimum temperature at Rockhampton Aero (BOM) ......................106
Figure 38. Rockhampton Aero Mean Rainfall (BOM) ......................................................................... 107
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Wulguru Technical Services Pty Ltd – Supporting Information Report
Figure 39. Rockhampton Aero 9am and 3pm Wind Rose (BOM 2023) ............................................. 108
Figure 40. Geological Map (WSP Design Report) .............................................................................. 109
Figure 41. Soil Types Mount Morgan Area (ASRIS Level 4 Australian Soil Classification)................110
Figure 42. Groundwater Levels and Flow Contours (Robertson Geoconsultants 2010) ....................114
Figure 43. Location of Groundwater Monitoring Bores (GHD, 2024) ................................................. 115
Figure 44. Upper Mundic Gully Conceptual Site Model ...................................................................... 118
Figure 45. Recharge Zones Assumed for model calibration............................................................... 126
Figure 46. Population survey and mapped habitat for Grevillea hockingsii within TSF footprint (GHD)
............................................................................................................................................................ 133
Figure 47. Population survey and mapped habitat for Cycas megacarpa within TSF footprint (GHD)
............................................................................................................................................................ 134
Figure 48. Sensitive Receptor Map (GHD) ......................................................................................... 156
Figure 49. Cultural Heritage Features................................................................................................. 162
Figure 50. Waste and Resource Management Hierarchy................................................................... 188
Figure 51. Estimated Scope 1 and 2 Emissions by Year.................................................................... 192
Figure 52. GHG Abatement Hierarchy (Source: DETSI, 2025) .......................................................... 194
Figure 53. ISO 31000: 2018 Risk management process .................................................................... 197
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Wulguru Technical Services Pty Ltd – Supporting Information Report
1. Introduction
Wulguru Technical Services Pty Ltd (WTS) was engaged by Heritage Minerals Pty Ltd owner and
operator of the Mount Morgan Mine, to prepare supporting information for amendments to
Environmental Authority (EA) EPML00433013, current 26 May 2025.
This supporting information report is submitted to the Department of Environment and Science (DETSI)
in support of Heritage Mineral’s application to amend the EA. This supporting information report has
been produced to satisfy requirements of section 226 and 226A of the Environmental Protection Act
1994 (EP Act) specifically to provide:
• A detailed description of the proposed EA amendments; and
• An assessment of the potential impacts to relevant environmental values, as well as detailing
any relevant managed strategies associated with the proposed EA amendments.
This document complies with the following guidelines:
• Approval processes for Environmental Authorities (DES 2019b);
• Application requirements for activities with impacts to air (DES 2017a);
• Application requirements for activities with impacts to land (DES 2017b);
• Application requirements for activities with impacts to water (DES 2017c);
• Application requirements for activities with noise impacts (DES 2017d); and
• Application requirements for activities with waste impacts (DES 2019a).
1.1. Purpose
The purpose of this document is to describe the existing environmental values and assess the potential
environmental impacts that may arise from the proposed amendments. The proposed amendments
relate to:
• Authorise Upper Mundic Gully TSF by inclusion as a mine feature in the EA;
• Update Table A1, and associated Schedule I Figure 1, to address to be determined (TBDs)
associated with the pipe corridor and exploration mine features; and
• Fix minor erroneous issues in the EA that impact on the processed tailings volumes for
discharge into Sandstone Gully TSF.
The Queensland Environmental Regulator Regulatory Strategy 2022-2027 articulates that a key focus
area for DETSI is to “Regulate proportionate to risk”. To align with this focus area, this supporting
information report provides a risk assessment that has been completed to identify potential impacts of
the proposed amendments and appropriate mitigation measures. A summary of the risks and likely
magnitude of impacts on environmental values is included in Section 2.4 whilst the full risk assessment
is provided in Section 7.
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Wulguru Technical Services Pty Ltd – Supporting Information Report
Throughout this document reference is made to the Upper Mundic Gully TSF (the project) and the
Heritage Minerals Tailings Reprocessing (the overall project).
1.2. Project Location
The Mount Morgan Mine is located near the town/location of Mount Morgan 38 kilometres south west
of Rockhampton in Central Queensland. A site locality map is provided in Figure 1. The Mount Morgan
Mine is largely bound to the east by the Dee River and bound to the north and west by undulating hills.
Mount Morgan was founded as a gold mining town in 1882, with the Mount Morgan Mine located directly
adjacent to the west. In addition to mining resources, the predominant land uses in the surrounding
region is cattle grazing within native vegetation, with some areas of forestry and irrigated cropping.
This region experiences a sub-tropical climate, with distinctive wet and dry seasons, with approximately
70 percent of rain fall during the wet season (between November and April). The Mount Morgan Mine
is located alongside the Dee River, forming part of the Dee River Catchment. The catchment forms part
of the larger Fitzroy River system within the Fitzroy River basin. The Dee River generally flows south to
west into the Don River and Dawson River before reaching the Fitzroy River where it enters the ocean
at Port Alma, downstream of Rockhampton.
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Wulguru Technical Services Pty Ltd – Supporting Information Report
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