BHP : BWM North Extension Project – EA Amendment Application

BLACKWATER MINE

Blackwater Mine -

North Extension Project

Environmental Authority Amendment Supporting

Information Document

Status: Submission

Version: 1.0

Document Control

Reference	Date	Prepared	Checked	Authorised
BWM EA Amendment Supporting	14/12/2023	SLR and BMA
Document

Blackwater Mine - North Extension Project Environmental Authority Amendment Supporting Information

Table of Contents

Abbreviations	xii
1	Introduction	1
	1.1	The Application for Amendment	1
	1.2	The Proponent	1
	1.3	Existing BWM Operations	4
	1.4	Project Overview	5
	1.5	Project Objectives	5
	1.6	Structure of this Document	5
2	Regulatory Considerations	7
	2.1	Primary State Legislation	7
		2.1.1 Mining and Environmental Legislation	7
		2.1.2	Mineral Resources Act 1989	7
		2.1.3	Environmental Protection Act 1994	8
	2.2	Other State Legislation	16
		2.2.1	Water Act 2000	16
		2.2.2	Environmental Offsets Act 2014	17
		2.2.3	Planning Act 2016	18
		2.2.4	Regional Planning Interests Act 2014	18
		2.2.5	Fisheries Act 1994	18
		2.2.6	Nature Conservation Act 1992	19
		2.2.7	Vegetation Management Act 1999	19
		2.2.8	Biosecurity Act 2014	20
	2.3	Commonwealth Environment Protection and Biodiversity Conservation Act 1999	20
	2.4	Cultural Heritage and Native Title	21
		2.4.1	Queensland Heritage Act 1992	21
		2.4.2	Queensland Aboriginal Cultural Heritage Act 1993	21
		2.4.3	Native Title Act 1993	22
	2.5	Assessment Methodology	22
		2.5.1 Overview of assessment methodology	22
		2.5.2	Environmental Assessments	22
	2.6	Community Engagement and Project Consultation Activities	23
3	Project Description	24
	3.1	Overview of Existing Operations	24
		3.1.1	Mining Tenure	24
		3.1.2 Mine Method, Run of Mine and Product Coal Tonnages	24
		3.1.3 Coal Handling and Preparation	25
		3.1.4 Production and Supporting Infrastructure	26
		3.1.5 Rejects and Tailings Management	26
		3.1.6	Electricity Supply	26
		3.1.7 Mine Water Management, Water Supply and Demand	27
		3.1.8	Sewage Treatment	29
		3.1.9 Fuel and Lubricant Storage and Dispensing	29

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		3.1.10	Environmental Authority	29
	3.2	Proposed Project	30
		3.2.1	Introduction	30
		3.2.2	Mining Tenure	30
		3.2.3	Land Ownership within SA10 and SA7	30
		3.2.4	Resource Characterisation	33
		3.2.5	Mining Methods and Sequence	35
		3.2.6	Waste Rock Management	37
		3.2.7	Run of Mine and Product Coal Production Schedule	37
		3.2.8	Coal Handling and Preparation	48
		3.2.9	Rejects and Tailings Management	48
		3.2.10	Final Voids	48
		3.2.11	Mining Equipment	48
		3.2.12	Blasting	50
		3.2.13	Workforce Requirements and Accommodation Arrangements	50
		3.2.14	Hours of Operation	50
		3.2.15	Project-Specific Mine Infrastructure	51
		3.2.16	Flood Protection	53
4	Rehabilitation	54
	4.1	Progressive Rehabilitation and Closure Plan	54
	4.2	Key Information	55
	4.3	Conceptual Final Landform	56
	4.4	Rehabilitated Landform Options Assessment	57
		4.4.1	Final Void - Endwall Backfill for Flood Mitigation	59
		4.4.2	Progressive Backfilling of Void	59
	4.5	Proposed Land Outcomes	59
		4.5.1	Post-Mining Land Use	59
		4.5.2	Non-Use Management Areas	60
	4.6	Rehabilitation Activities	61
		4.6.1	Topsoil Management and Surface Preparation	61
		4.6.2	Revegetation	63
	4.7	Rehabilitation Schedule	65
	4.8	Rehabilitation Goals, Milestones and Completion Criteria	68
		4.8.1	Rehabilitation Goals	68
		4.8.2	Rehabilitation Objectives, Indicators and Acceptance Criteria	68
		4.8.3	Rehabilitation Areas, Improvement Areas and Milestones	68
		4.8.4	Monitoring, Maintenance and Reporting	72
	4.9	Exploration Areas	72
5	Project Justification and Alternatives	73
	5.1	Justification	73
	5.2	Alternatives	74
		5.2.1	Project Location	74
		5.2.2	Full Footprint Development	74
		5.2.3	Non-Constrained Mine Plan - Sensitive Vegetation	74
		5.2.4	No Project	75

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5.3	Standard Criteria Assessment	75
	5.3.1	Criterion (a) - Ecologically Sustainable Development	76

5.3.2 Criterion (b) - Applicable Commonwealth, State or Local plans, Standards,

	Agreements or Requirements	80
5.3.3	Criterion (d) - Environmental Impact Study	82

5.3.4 Criterion (e) - Character, Resilience and Values of Receiving Environment..82

		5.3.5	Criterion (f) - Submissions made by Applicant and Submitters	82
		5.3.6	Criterion (g) - Best Practice Environmental Management	82
		5.3.7	Criterion (h) - Financial Implications	83
		5.3.8	Criterion (i) - Public Interest	83
		5.3.9	Criterion (j) - Site Management Plan	83
		5.3.10	Criterion (k) - Proposed integrated environmental management system	83
		5.3.11	Criterion (l) - Other matters	83
6	Land Resources	84
	6.1	Introduction	84
	6.2	Environmental Values	84
		6.2.1	Climate	84
		6.2.2	Topography	84
		6.2.3	Vegetation and Land-Use	84
		6.2.4	Land Systems	84
		6.2.5	Soil Classification and Description	85
	6.3	Potential Impacts to Land Resources	87
		6.3.1	Land Suitability	87
		6.3.2	Agricultural Land	87
		6.3.3	Land Capability	88
		6.3.4	Grazing Suitability	88
	6.4	Mitigation and Management Measures	89
		6.4.1	Rehabilitation	89
		6.4.2	Land Resources Mitigation Measures	92
7	Geochemistry	93
	7.1	Introduction	93
	7.2	Assessment Methodology	93
	7.3	Environmental Values	94
		7.3.1	Geochemical Characteristics of Non-Carbonaceous Mineral Waste	94
		7.3.2	Geochemical Characteristics of Carbonaceous Spoil	95
		7.3.3	Geochemical Characteristics of Tailings	96
		7.3.4	Geochemical Characteristics of RoM Coal	97
	7.4	Potential Impacts	98
	7.5	Mitigation and Management Measures	98
		7.5.1	Management and Mitigation of Spoil	98
		7.5.2	Management and Mitigation of Tailings	99
		7.5.3	Management and Mitigation of Coarse Reject	99
		7.5.4	Validation of Tailings and Coal Reject Characteristics	99
		7.5.5	Management of RoM Coal and RoM Stockpiles	99

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8	Air Quality	....................................................................................................	101
	8.1	Introduction	101
	8.2	Environmental Values	101
		8.2.1	Existing Receptors	101
		8.2.2	Existing Air Quality Environment	104
		8.2.3	Assessment Criteria	106
	8.3	Air Quality Assessment Methodology	106
		8.3.1	Dust Emission Sources	106
		8.3.2	Dust Emission Scenarios	107
		8.3.3	Dust Emissions Inventory	107
		8.3.4	Overview of Dispersion Modelling	107
	8.4	Potential Impacts	111
		8.4.1	Dust Deposition	111
		8.4.2	Particulate Matter as TSP	112
		8.4.3	Particulate Matter as PM10	113
	8.5	Mitigation and Management Measures	114
		8.5.1	Existing Dust Management	114
		8.5.2	Key Drivers to Dust Risk	115
		8.5.3	Modelled PM10 Mitigation Scenarios	116
		8.5.4	Comparison of the Project With (BAU) and (Fully Mitigated) Cases	118
		8.5.5	Project Dust Management	119
	8.6	Greenhouse Gas Emissions	120

9	Noise and Vibration	121
	9.1	Introduction	121
	9.2	Environmental Values	121
		9.2.1	Existing Receptors	121
		9.2.2	Existing Acoustic Environment	121
		9.2.3	Noise and Vibration Assessment Criteria	125
	9.3	Noise and Vibration Assessment Methodology	126
		9.3.1	Noise and Vibrating Project Activities	126
		9.3.2	Noise Modelling Scenarios	126
		9.3.3	Noise Prediction Modelling	127
		9.3.4	Cumulative Noise Impact Assessment	128
		9.3.5	Blasting	128
	9.4	Potential Impacts	128
		9.4.1	Predicted Operational Noise Levels	128
		9.4.2	Cumulative Noise Levels	133
		9.4.3	Blasting	135
	9.5	Mitigation and Management Measures	136
		9.5.1	Operational Mine Noise	136
		9.5.2	Cumulative Noise	139
		9.5.3	Blasting	139

10	Surface Water	140
	10.1 Introduction	140

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	10.2	Environmental Values	140
		10.2.1	Regional and Local Hydrology	142
		10.2.2	Water Quality Monitoring	144
		10.2.3	Water Quality in Mine Affected Water Storages	147
		10.2.4	Existing Water Users	147
		10.2.5	Creek Geomorphology	147
	10.3	Surface Water Management	149
		10.3.1	Surface Water Management Strategy	149
		10.3.2	Surface Water Storage	149
		10.3.3	Flood Protection	151
	10.4	Potential Impacts	153
		10.4.1	Flooding	153
		10.4.2	Changes to Stream Flows	156
		10.4.3	Changes to Groundwater - Surface Water Interactions	159
		10.4.4	Mine Water Releases	159
		10.4.5	Water Quality Impacts	161
		10.4.6	Great Barrier Reef Considerations	161
		10.4.7	Final Void Assessment	161
		10.4.8	EPBC Act Significant Impact Assessment	162
		10.4.9	Cumulative Impacts	162
		10.4.10	Climate Change	162
	10.5 Mitigation and Management Measures	162
11	Groundwater	165
	11.1	Introduction	165
	11.2	Environmental Values	165
		11.2.1	Environmental Values and Water Quality Objectives	165
		11.2.2	Geology	167
		11.2.3	Local Hydrostratigraphic Units	172
		11.2.4	Groundwater Levels and Flow Directions	172
		11.2.5	Hydraulic Properties	174
		11.2.6	Groundwater-Surface Water Interactions	174
		11.2.7	Groundwater Quality	176
		11.2.8	Groundwater Use	178
	11.3	Potential Impacts	183
		11.3.1	Groundwater Numerical Model	183
		11.3.2	Groundwater Inflows to Open Cut Pits	184
		11.3.3	Groundwater Drawdown	184
		11.3.4	Influence on Alluvium	185
		11.3.5	Impacts on Groundwater Users	191
	11.4 Mitigation and Management Measures	195
		11.4.1	Groundwater Quality	195
		11.4.2	Groundwater Use	195
		11.4.3	Groundwater Monitoring Program	196
		11.4.4	Data Management and Reporting	197
12	Terrestrial Ecology	198

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	12.1	Introduction	198
	12.2	Regional and Local Setting	198
	12.3	Methodology	198
		12.3.1	Desktop Assessment	198
		12.3.2	Field Survey	199
	12.4	Environmental Values	202
		12.4.1	Terrestrial Flora	202
		12.4.2	Terrestrial Fauna	212
		12.4.3 Threatened and CEEVNT Fauna	213
		12.4.4	Matters of National Environmental Significance	221
		12.4.5 Matters of State Environmental Significance	222
	12.5	Potential Impacts	224
		12.5.1 Vegetation Clearing and Habitat Disturbance	224
		12.5.2	Fragmentation	225
		12.5.3	Erosion and Sedimentation	225
		12.5.4	Bushfire	226
		12.5.5	Noise, Dust and Lighting	226
		12.5.6	Weeds and Pests	227
		12.5.7	Fauna Mortality	227
		12.5.8	Groundwater Drawdown	227
	12.6	Mitigation and Management Measures	230
	12.7	Significant Impact Assessments	232
		12.7.1	Matters of National Environmental Significance	233
		12.7.2 Matters of State Environmental Significance	236
13	Aquatic Ecology and Stygofauna	237
	13.1	Introduction	237
	13.2	Regional and Local Setting	237
	13.3	Methodology	237
		13.3.1	Baseline Surveys	237
		13.3.2	Desktop Assessment	239
	13.4	Environmental Values	241
		13.4.1	Waterways	241
		13.4.2 Lacustrine Wetlands and Farm Dams	242
		13.4.3	Palustrine Wetlands	243

13.4.4 High Ecological Significance Wetlands and Wetlands of International or

	National Importance	243
13.4.5	Water Quality	243
13.4.6	Sediment Quality	243
13.4.7	Aquatic Biota	244
13.4.8	Special Least Concern Species	245
13.4.9	Surface Expression GDEs	245
13.4.10	Stygofauna and Subterranean GDEs	245
13.4.11	Matters of National Environmental Significance	245
13.4.12	Matters of State Environmental Significance	246
13.5 Potential Impacts	248

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		13.5.1	Aquatic Habitat Modification and Loss	248
		13.5.2	Fish Passage	248
		13.5.3	Water Management Strategy and MAW Releases	249
		13.5.4	Surface Water Quality	249
		13.5.5	Surface Water Run-off of Seepage from Spoil	250
		13.5.6	Flow Regime	250
		13.5.7	Flood Regimes	250
		13.5.8	Litter and Waste	251
		13.5.9	Proliferation of Aquatic Pests	251
		13.5.10	Aquatic GDEs	251
		13.5.11	Matters of National Environmental Significance	252
		13.5.12	Matters of State Environmental Significance	252
	13.6	Mitigation and Management Measures	253
14	Waste Management	257
	14.1	Introduction	257
	14.2	Waste Management Objectives	257
	14.3	Waste Management Strategy	257
	14.4	Waste Management Plan	258
		14.4.1	Waste Avoidance and Minimisation	259
		14.4.2	Waste Segregation	259
		14.4.3	Waste Reuse, Recycle and Recovery	260
		14.4.4	Waste Disposal	260
	14.5	Waste Production	261
	14.6	Summary of Mitigation Measures and Commitments	261
	14.7	Conclusion	261
15	Environmental Authority Amendments	267
	15.1	EA Condition E23	267
	15.2	EA Condition I1	267
	15.3	EA Condition I2	267
References	.............................................................................................................	269
Glossary		278

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List of Figures
Figure 1-1:	Project Location	2
Figure 1-2:	Project Overview	2
Figure 2-1:	Category B ESA - DES mapping within Project area	13
Figure 2-2:	Category B ESA, Ground-Truthed Vegetation Mapping within Project area	14
Figure 3-1:	Blackwater Mine - Typical Mining Sequence	24
Figure 3-2:	BWM Operation Process Schematic	25
Figure 3-3:	BWM Mine Water Management System Schematic	28
Figure 3-4:	Land Ownership SA7 and SA10	32
Figure 3-5:	Schematic Seam Stratigraphy and Split Diagram	34
Figure 3-6:	Indicative BWM Materials Schedule - FY2025 to FY2085	38
Figure 3-7:	Indicative Project Mining Progression	39
Figure 3-8:	Indicative Project Mining Progression at FY2025	40
Figure 3-9:	Indicative Project Mining Progression at FY2035	41
Figure 3-10:	Indicative Project Mining Progression at FY2045	42
Figure 3-11:	Indicative Project Mining Progression at FY2055	43
Figure 3-12:	Indicative Project Mining Progression at FY2065	44
Figure 3-13:	Indicative Project Mining Progression at FY2075	45
Figure 3-14:	Indicative Project Mining Progression at FY2085	46
Figure 3-15:	Indicative Conceptual Final Landform	47
Figure 4-1:	Indicative Residual Void Cross Section	58
Figure 4-2:	Conceptual Post-Mining Land Use	62
Figure 4-3:	Schematic of Mine and Spoil Dump Progression	67
Figure 8-1:	Project Area and Receptor Locations	103
Figure 8-2:	DES Blackwater monitoring station data - 24 hour average concentration of PM10	105
Figure 8-3:	Air Quality Assessment Locations (Detailed Results)	110
Figure 8-4:	Project With (BAU) Case: Key Drivers based on an Average over the LoM	116
Figure 9-1:	EMM Noise Monitoring Locations (EMM, 2021)	122
Figure 10-1:	Upper Mackenzie Sub-catchment of the Fitzroy Basin	141
Figure 10-2:	Local Waterways	145
Figure 10-3:	Water Quality Monitoring Locations	146
Figure 10-4:	Water Users	148
Figure 10-5:	Water Management Diagram	150
Figure 10-6:	Proposed Flood Protection Locations	152
Figure 10-7:	Extension Conditions Peak Flood Levels 0.1% AEP	154
Figure 10-8:	Extension Conditions Peak Flood Afflux 0.1% AEP	155
Figure 10-9:	Extension Conditions Climate Change Peak Flood Afflux 0.1% AEP	157
Figure 10-10:	Final Landform Peak Flood Depths 0.1% AEP	158
Figure 10-11:	Potential Change in Stream Flow	159
Figure 11-1:	Groundwater Management Areas and Chemistry Zones	166
Figure 11-2:	Surface Geology	168
Figure 11-3:	Solid Geology	169
Figure 11-4:	Geological Cross Section across the Groundwater Study Area	171
Figure 11-5:	Groundwater Monitoring Network	173

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Figure 11-6:	Groundwater Level Contours in the Aries Seam and Pit Lake Elevations
	(March 2023)	175
Figure 11-7:	Private Bores	179
Figure 11-8:	Predicted Terrestrial Groundwater Dependent Ecosystems	181
Figure 11-9:	Mapped Potential Aquatic GDEs in the Vicinity of the Project	182
Figure 11-10: Maximum Incremental (a) and Cumulative (b) Drawdown in the Alluvium and
	Tertiary (Layer 1)	186
Figure 11-11: Maximum Incremental (a) and Cumulative (b) Drawdown in the Alluvium and
	Tertiary (Layer 2)	187
Figure 11-12: Maximum Incremental (a) and Cumulative (b) Drawdown in the Aries Seam
	(Layer 8)	188
Figure 11-13: Maximum Incremental (a) and Cumulative (b) Drawdown in the Pollux Seam
	(Layer 12)	189
Figure 11-14: Maximum Incremental (a) and Cumulative (b) Drawdown in the Burngrove
	Formation (Layer 14)	190
Figure 11-15: Indicative Final Void Locations	192
Figure 11-16: Groundwater Table Recovery (200 years Post-Mining)	193
Figure 12-1:	Desktop Search Area and Bioregions	200
Figure 12-2:	Ground-truthed Regional Ecosystems	204
Figure 12-3:	Brigalow TEC	208
Figure 12-4:	Threatened Flora - Solanum elachophyllum	209
Figure 12-5:	Potential TGDE Communities in and adjacent to the Project area	211
Figure 12-6:	Habitat Mapping - Australian Painted Snipe	215
Figure 12-7:	Habitat Mapping - Ornamental Snake	216
Figure 12-8:	Habitat Mapping - Squatter Pigeon	217
Figure 12-9:	Habitat Mapping - Koala	218
Figure 12-10:	Threatened and Migratory Fauna Observations	220
Figure 12-11:	Assessed Likelihood of Impact if Identified Potential GDEs	229
Figure 13-1:	Aquatic ecology sites and stygofauna bores surveyed in the baseline
	monitoring for the Project	238
Figure 13-2:	BWM REMP Sites	240
Figure 13-3:	Waterway Barrier Works mapping in the vicinity of the Project	247
Figure 14-1:	Waste management hierarchy	259
List of Tables
Table 2-1:	Minor EA Amendment Threshold Criteria	9
Table 2-2:	EIS Trigger Assessment for the Project	11
Table 2-3:	DES and DCCEEW Consultation Activities	23
Table 3-1:	Blackwater Mine - Typical Pit Design Criteria	25
Table 3-2:	BWM - Existing Mine Water Management Overview	27
Table 3-3:	Project Area Mining Tenements	30
Table 3-4:	Land Ownership within SA10 and SA7	31
Table 3-5:	JORC Classified Resources for BWM (30 June 2023)	35
Table 3-6:	JORC Classified Reserves for BWM (30 June 2023)	35
Table 3-7:	Indicative Mining Fleet and Equipment	49

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