BHP Billiton Nickel West Leinster Operations (L4612/1989/11)

Works Approval Application Supplementary Information TSF Cell F

APPLICATION ATTACHMENTS 1A, 1B, 2, 3A, 6, 7, 8 and 9. JULY 2019 Table of Contents

1.Purpose of Document 4

2.Premises Details 5 2.1 Location 5 2.2 Prescribed Premises Category 5 2.3 Other approvals, legislation and guidance 8

3.Description of Proposed Activity 9 3.1 Scope of works 9 3.1.1 Embankment materials and staging 9 3.1.2 Tailings delivery and distribution 10 3.1.3 Seepage interception system 10 3.1.4 Decant system 10 3.1.5 Return water pond 11 3.2 Supporting infrastructure 11 3.3 Timing and implementation 12

4.Existing Environment 14 4.1 Climate 14 4.2 Hydrology 15 4.3 Hydrogeology and groundwater 16 4.4 Landforms and soil types 17 4.5 Flora and vegetation 17 4.6 Social environment 18 4.6.1 Aboriginal and European heritage 18

5.Emissions and Discharges 19 5.1 Dust 19 5.2 Waste management 19 5.3 Water management 19 5.3.1 Stormwater diversion 19 5.3.2 Discharge 21 ii 5.4 Groundwater 21

6.Risk assessment 23 6.1 Environmental Management of TSFs 28

7.Fee calculation 29

APPENDIX A: Proof of Occupier Status (Attachment 1A) 31

APPENDIX B: ASIC Company Extract (Attachment 1B) 32

APPENDIX C: TSF Cell F Design Drawings, Figures F001 – F015 33

APPENDIX D: Design Report in Support of Mining Proposal and Works Approval Application (1788205- 037-R-Rev2) Golders July 2019 34

APPENDIX E: Flora and Vegetation Mapping 35

List of Tables

Table 1: Schedule of Works Approval Application Attachments ...... 4 Table 2: Prescribed Premises Categories under Current Licence ...... 5 Table 3 Summary of TSF Project Infrastructure ...... 11 Table 4 TSF Cell F indicative filling schedule ...... 12 Table 5 IFD design rainfall depths (mm) for NLN site...... 15 Table 6: Risk Assessment ...... 24 Table 7: NiW TSF Design and Construction Information ...... 28 Table 8 TSF Cell F Construction Costs ...... 29 Table 9: Fee calculation ...... 29

List of Figures

Figure 1: Leinster Nickel Operations TSF Cell F ...... 6 Figure 2 Leinster prescribed premises boundary ...... 7 Figure 3 Mean climate statistics for Leinster air (BoM 2017) ...... 14 Figure 4 IFD curves for rainfall intensity and rainfall depth used in design ...... 15 Figure 5 Intermediate rainfall depths for 2% AEP to PMP ...... 16 Figure 6 Drainage lines at TSF Cell F ...... 19 Figure 7 Hydrological overview of TSF Cell F ...... 20

iii 1. Purpose of Document

BHP Billiton Nickel West Pty Ltd (NiW) is planning to develop a new tailings storage facility (TSF) at the Leinster Nickel Mine (NLN), located within the Shire of Leonora, 370 km north of Kalgoorlie. The new TSF is referred to as ‘Cell F’, and it is required to supplement the existing TSFs at NLN in order to accommodate expected tailings to be generated until 2040.

This document provides supplementary information to NiW’s Application for Works Approval for L4612/1989/11 and to meet the requirements of the DWER Application form, as shown in Table 1.

Table 1: Schedule of Works Approval Application Attachments

DWER Description Location within this Application Supplementary Information Attachment # Document 1A Proof of occupier status Appendix A 1B ASIC Company Extract Appendix B 2 Map of Premises Figure 2 3A Description of Activities Section 3 6A Emissions and Discharges Section 5 7 Siting and Location Figure 1; and Appendix C 8 Other relevant information Sections 2-4 9 Fee Calculation Section 7

iv 2. Premises Details

2.1 Location

The NiW Leinster Operations are located predominately on Mineral Lease 255SA , which is tenure granted under the State Agreement ratified by the Nickel (Agnew) Agreement Act 1974 (WA) (State Agreement). The TSF Cell F is located on ML255SA and on G36/49 and G36/50 (to be granted under the Mining Act 1978 (WA) (Mining Act), pursuant to the State Agreement), as shown in Figure 1. 2.2 Prescribed Premises Category

NiW Leinster currently holds Environmental Protection Act 1986 Licence L4612/1989/11 and is prescribed under the categories listed in Table 2.

The prescribed premises categories will not change with these works, however the prescribed premises boundary will require amendment to include the pending general purpose area G36/50. Tailings storage facilities are constructed and operated under Category 5. Refer to Figure 2 for the prescribed premises boundary.

Table 2: Prescribed Premises Categories under Current Licence

Category Number Description Throughput Classification

5 Processing or beneficiation 3,600,000 tonnes per year (ore of metallic or non-metallic processed) ore 6 Mine dewatering 2,000,000 tonnes per year 57 Used tyre storage 500 tyres or less 64 Class II putrescible landfill 20 tonnes or more per year 85 Sewage facility 44 m3 per day

v Legend D Proposed TS F CellF BHP Tenements LJ Ap plication CJ Granted

Figure 1: Leinster Nickel Operations TSF Cell F

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270000 272000 274000 276000 278000 280000 282000

8HP NIW -Ho1tMm Op.eu11lOII$ Legend BHP Nickel West 0 L4612/1989/11 •.i.... - Nickel West leinster Nickel Operation !""" ·"'""""""' PREMISES BOUNDARY ~~Cll41~-z-:--...... ,_ ._ ,. ~ ,..,_ , n n "' ,_ s.-ft,N.. '''°.- II"!_,.... SJW -- - o... , U'OVJOtt I I __ , ___ ,,__,.._,~---

Figure 2 Leinster prescribed premises boundary vii 2.3 Other approvals, legislation and guidance

Activities on ML255SA are approved by the Minister for State Development, Jobs and Trade, and the State Agreement is administered by the Department of Jobs, Tourism, Science and Innovation (JTSI). NiW operates the Leinster mining operations, including ore processing and tailings storage, under a range of Additional Proposals, approved by the Minister.

Pursuant to Clause 17(2) of the State Agreement NiW has requested JTSI to grant or arrange for the grant of two general purpose leases (reference G36/49 and G36/50) (GPLs) under the Mining Act, which is required to support the development of the new tailings cell, TSF Cell F and associated infrastructure. The two general purpose leases have a combined area of 27.5 hectares.

As a minor portion of TSF Cell F is on Mining Act tenure, approval of a Mining Proposal for the planned infrastructure on the GPLs is also required. The existing native vegetation clearing permit CPS 8008/3 will be amended to cover clearing within G36/50 and, if required, a native vegetation clearing permit will be sought to cover clearing within G36/49 (refer Figure 1).

Water abstraction activities, including for dewatering and potable supply, are undertaken in accordance with Licences to Take Water issued under the Rights in Water and Irrigation Act 1914, GWL58111(5), 63834 (4) and 66248(5).

TSF Cell F is not a significant proposal and does not require referral to the EPA under Part IV of the Environmental Protection Act 1986 (EP Act).

Further to the EP Act, this application takes into consideration the requirements of: · Environmental Protection Regulations 1987; · NiW Leinster EP Act Licence (L4612/1989/11); · Native Vegetation Clearing Permit CPS222/4; and · Department of Water and Environmental Regulation Guidance Statement – Risk Assessments (February 2017).

viii 3. Description of Proposed Activity

BHP NiW (NiW) is planning to develop a new tailings storage facility (TSF) at the Leinster Nickel Mine (NLN), located within the Shire of Leonora, 370 km north of Kalgoorlie. TSF Cell F is required to supplement the existing TSFs at NLN in order to accommodate expected tailings to be generated until 2040.

There are currently four operational TSFs at NLN: TSF2, TSF 3AB, TSF 3CD, and TSF 3E, with tailings deposition being rotated between them. TSF 3AB and TSF 3CD are approaching their final heights and supplementary tailings capacity is therefore required as part of NiW’s strategic planning to financial year (FY) 2040. It is proposed that TSF Cell F and additional future cells provide this capacity, refer Appendix C for TSF Cell F design drawings. 3.1 Scope of works

The proposed TSF Cell F is designed to accommodate up to approximately 29 Mt of tailings over a period of 20 years (2021-2040). It has been designed in accordance with recognised tailings-related guidelines for the development of TSFs in Western Australia. TSF Cell F is classified as ‘Significant’ in terms of ANCOLD and a ‘Significant Hazard, Category 1’ facility in terms of DMIRS guidelines and associated code of practice. Refer Appendix D for the TSF Cell F Design Report containing Tailings Storage Data Sheet and certification that the TSF Cell F design complies with the required safety guidelines.

TSF Cell F is planned to be constructed as an above-ground impoundment, which will be progressively developed in discrete stages. The initial starter embankment (Stage 1A) will be raised in a downstream direction, with two main embankments constructed to the north and east. Stage 1B will involve the construction of the southern and western embankments. Stages 1A and 1B embankments will be formed from compacted mine waste. Subsequent stages (7 proposed lifts) of TSF Cell F development will be constructed in an upstream (inward) direction from compacted tailings sourced from the adjacent tailings beaches, mimicking the procedure that has been adopted for the existing TSF cells. Cell F will provide tailings storage capacity to maintain a rate of rise of on average 1.5m/yr (refer Appendix C, Figure 008). 3.1.1 Embankment materials and staging

A typical cross-section through the TSF Cell F embankment is shown on Appendix C, drawing F005. Stage 1A will be constructed to relative level (RL) 10 516.0 m to accommodate an initial (continuous) ~12 months of tailings deposition at an estimated average rate of 4850 t/day of insoluble solids, at around 35 to 40% solids by mass. It should be noted that deposition rate may vary up to a maximum rate of 8,000 t/day, thereby reducing the time required to fill Stage 1A.

Thereafter, tailings deposition will revert to the other operational TSFs and the Stage 1B embankment will be constructed to RL 10 520 m. A temporary bund will be constructed across the basin at Stage 1A to divert stormwater runoff from entering the TSF Cell F basin.

Both Stages 1A and 1B embankments will be constructed from imported mine waste, which will be compacted to form a low permeability confining embankment, capable of storing water for a limited period of time. A cut-off key will be formed below Stage 1A down to caprock, limiting the potential for seepage under the embankment.

Following filling of the basin of TSF Cell F to the operational freeboard limit for Stage 1B, six progressive upstream raises of approximately 2.5 m in height and one final raise of approximately 2.8 m will be constructed, as required through the deposition schedule, refer 3.1.2. The upstream raises will be constructed from compacted tailings, sourced predominately from the adjacent beaches, mimicking the process that has been successfully implemented at NLN for all existing TSFs since the 1970s. The final crest elevation of TSF Cell F is expected to be approximately RL 10 537.8 m.

ix 3.1.2 Tailings delivery and distribution

Appendix C, Figure F006 shows the proposed tailings delivery pipeline route and distribution system around TSF Cell F. The pipeline will be connected to the existing tailings delivery pipeline at the south-western corner of TSF Cell F (north-western corner of TSF 3AB) before bifurcating, with one pipeline feeding the southern and eastern flanks, and one pipeline feeding the western and northern flanks of TSF Cell F.

Spigots will be installed along the pipelines at approximately 40 m centres. The spigots will be opened/closed by means of gate valves. It is expected that five to six adjacent spigots will be opened at any one time to result in uniform beaching, free of significant gullies. To reduce erosion of the upstream (internal) faces of the starter embankments and internal toe drain, 110 mm diameter uPVC12 ‘conductor pipes’ will be placed on the faces, into which the tailings slurry will discharge after flowing through an open spigot and length of flexible rubber hosing. The conductor pipes will direct slurry so that it is discharged at the lowermost opening in the conductor pipes. 3.1.3 Seepage interception system

Appendix C, Figure F007 shows the proposed location and cross-section, as well as outlet locations of the internal toe drain that will be provided to collect tailings consolidation water, manage seepage, and control the location of the phreatic surface. The toe drain comprises a filter sand zone, 3 m in width, placed at the upstream (internal) toe of the starter embankment along the northern and eastern flanks of TSF Cell F.

The western flank does not require a drain, as the natural ground topography slopes inwardly along that flank. In addition, it is planned to infill between the external slope and waste rock stockpiles along the western flank to form an integrated waste landform (refer Appendix C, Figure F004). The southern flank does not require a drain as the natural topography falls away from the northern toe of TSF 3AB, against which TSF Cell F will be formed. The outlet pipes will be extended as required on the outside of the TSF, so that they discharge into the RWP. 3.1.4 Decant system

Ultimately, a permanent decant structure, comprised of precast concrete rings surrounded by coarse rock, will be progressively raised in line with external cell wall lifts, within the centre of TSF Cell F. Decant water will flow into the decant inlet structure which flows into the gravity feed outfall pipeline to the return water pond, refer Appendix C, Figure F008.

The inlet system comprises a 1.8 m diameter tower, formed from precast concrete rings, 1.2 m in height. Numerous slots are formed in the concrete rings to allow water to enter the tower. To reduce the turbidity of decant water, coarse rock will be placed around the tower, drawing down the level of settled tailings solids.

As the height of tailings within TSF Cell F rise, additional concrete rings will be added to the tower, and additional rock placed surrounding it. For this reason, an access causeway to the decant inlet will be established to accommodate heavy vehicles for maintenance purposes. Within the concrete tower, there will be vertical riser of perforated pipe, to allow decanted water to flow into the gravity outfall pipe.

In the unlikely event of a threat of the return water pond (RWP) overtopping and spilling to the external environment, decant water can be temporarily held on the surface of the TSF. The decant pipe has been sized to decant water and stormwater from the TSF in a controlled manner and at a rate commensurate with the capacity RWP pumps returning water to the process plant for re-use.

In Stage 1A (for approximately 12 months), given the topography of the land, it is anticipated decant water will pond in the north-eastern corner of the TSF. This water will be removed by pumping to the existing RWP that services TSFs located at the northern flank of TSF 3AB, from where it will be returned to the process plant for re-use.

x A temporary access causeway will be built, varying between 1 m and 1.6 m in height above the cleared ground level to facilitate pumping of water from a sufficiently deep section of TSF. 3.1.5 Return water pond

The proposed return water pond (RWP) will collect decanted supernatant and rainwater from the surface of the TSF, as well as seepage water discharged from the toe drain. The RWP will be established adjacent to the northern wall of Cell F at the commencement of Stage 1b.

The pond has been sized to accommodate discharge of ten hours of water at full capacity from TSF Cell F, over and above a normal operating and dead storage volume, without overtopping ( approximately 10 000 m3). The RWP will be inspected each shift, and it is thus highly improbable that a malfunctioning/out-of-order pump would be inoperative whilst water inflow persists from the TSF for longer than this period. Telemetry will be installed to facilitate monitoring of flows from the RWP, and to enable remote checks for leaks in the return water pipeline.

To avoid seepage losses from the pond and to manage the risks of piping erosion of the RWP’s embankments, the RWP will be lined with a 2 mm thick HDPE geomembrane. An emergency spillway will be provided, although it is recognised that the likelihood of it being required is very low. Release from the RWP would be considered a non-conformity and require notification to DWER. The RWP will be surrounded by a cattle-proof security fence.

Upon establishment of TSF Cell F RWP, the existing RWP located at TSF 3AB will be decommissioned. The gravity outfalls from TSFs 3AB, 3CD and 3E, as well as underdrain flows from TSF 3, will all be extended through the basin of TSF Cell F and flow into the TSF Cell RWP. Refer Appendix C, Figure F009. 3.2 Supporting infrastructure

A summary of TSF Cell F Project Infrastructure is detailed in Table 3 below.

Table 3 Summary of TSF Project Infrastructure

Infrastructure Description / specification

1 TSF Cell F TSF Cell F constructed in stages 1A and 1B, followed by lifts 1 – 7, (refer Appendix C, F004, F005)

2 Return water pond TSF Cell F return water pond to be constructed post the completion of stage 1B (refer Appendix C, F009)

3 Surface water flow diversion drain Refer Appendix C, F010

4 Groundwater monitoring bores (x 6) Installation of four (4) groundwater monitoring bores to the north to replace existing monitoring bores north of TSF3 AB.

Installation of two (2) groundwater monitoring bores to the east of TSF Cell F

5 Recovery bore (minimum x 1) Installation of a minimum of one groundwater recovery bore (additional recovery bores may be installed if required) to replace existing recovery bores to the north of TSF 3AB

6 Drainage outlet pipes from existing Decant drainage pipelines from the existing TSFs TSFs installed through Cell F and commissioned following Stage 1B

xi 3.3 Timing and implementation

The proposed infrastructure works will commence construction immediately upon receipt of the following: a) Ministerial approval of the Additional Proposal for the works; b) grant of the GPLs for the works; c) approval of the Mining Proposal for the works; and d) approval of the Works Approval for the works.

It is expected that the TSF will become operational between January – June 2020

In order to maximise the storage capacity of TSF Cell F, the scheduling of deposition between TSF Cell F, and the TSF 2 and TSF 3 cells has been optimised. Once TSF Cell F is commissioned, it is currently proposed to rotate deposition between TSF 2 and TSF 3E. To avoid unacceptable marginal rates of rise on TSF 3E and to provide adequate drying time on TSF Cell F, TSF 2 and TSF 3E will be half filled. Deposition will then rotate to TSF Cell F to fill a complete 2.5 m raise, it will then revert back to TSF 2 and TSF 3E to complete the second half of the fill.

Table 4 provides an indicative fill schedule for TSF Cell F based on current operations. This schedule is indicative and may vary with future operational requirements and the potential development additional cells.

Table 4 TSF Cell F indicative filling schedule

Stage Crest RL Commence Storage Storage Rate of Sequence of deposition capacity life rise filling until next (approximate (Mm3) (days) (m/year) raise on Cell F years post commissioning of Stage 1A)

Stage 10 516.0 m 0 1.14 354 2.86 TSF 2, TSF 3E 1A – both cells will be filled to half capacity to allow rotation back to Cell F

Stage 10 520.0 m 1.7 2.88 915 1.25 TSF 2 then TSF 1B 3E – fill the second half of capacity

Lift 1 10 522.5 m 4.8 2.76 726 1.01 ½ TSF 2 and ½ TSF 3E

Lift 2 10 525.0 m 7.3 2.16 501 1.34 ½ TSF 2 and ½ TSF 3E

Lift 3 10 527.5 m 9.3 2.12 465 1.40 ½ TSF 2 and ½ TSF 3E

Lift 4 10 530.0 m 11.0 2.10 469 1.37 ½ TSF 2 and ½ TSF 3E

Lift 5 10 532.5 m 12.8 2.06 586 1.17 ½ TSF 2 and ½ TSF 3E

xii Lift 6 10 535.0 m 15.0 1.98 476 1.34 ½ TSF 2 and ½ TSF 3E

Lift 7* 10 537.5 m 16.8 2.16 647 1.03 ½ TSF 2 and ½ TSF 3E**

Notes: * Last lift on Cell F 2.8 m high, all other lifts are 2.5 m high ** Final lifts on TSF 2 and TSF 3E to take them to RL 10 560 m, currently the licenced final height

An alternative to half-filling of TSF 2 and TSF 3E would be to carry out half-height construction of those cells, i.e. to construct 1.25 m high embankment raises instead of the standard 2.5 m lifts. BHP will decide on the most economical alternative during project execution phase. Half-filling or half- raising of the TSF 2 and TSF 3E cells will not have negative impacts on the rates of rise of those facilities, and safety and stability will therefore not be compromised. The annualised rates of rise of both cells will remain below the target of 1.5 m/year.

xiii 4. Existing Environment

4.1 Climate

The NLN site lies within a semi-arid region, which experiences cool winters and hot summers. The Bureau of Meteorology (BoM) data for Leinster airport records the mean monthly range in daily minimum temperature as 6° to 23°C and the maximum temperature range as 19°C to 37°C (refer Figure 3). Wind strengths are generally moderate, averaging between 16 to 21 km/h throughout the year, and are typically easterly to north-easterly.

70 40

35 60

30 50

e 25 ~ g 40 e -- ...... / ~ 20 / i ~ E / 30 ...... / C i / 15 ~ / "' / 20 " / " 10

10

0 r,-t-tI Jan Feb Mar Apr May Jun Jul Aug Sep IOct INov Dec - Mean rainfall - Mean max. temperature - •Mean min. temperature

Figure 3 Mean climate statistics for Leinster air (BoM 2017)

High temperatures and low humidity throughout much of the year produce an average yearly pan evaporation rate of more than 3200 mm at Leinster. Average evaporation exceeds average rainfall in all months of the year. The long-term average annual rainfall is approximately 260 mm, although substantial variation occurs.

Mean monthly rainfall peaks during the summer months between January and March (up to 40 mm), and it is at its lowest in spring (refer Figure 3). Although intense rainfall can occur at any time of year, most of the rainfall in the area is associated with two distinct patterns:

I. Summer – Intensive rainfall can occur due to tropical lows, or localised thunderstorms associated with tropical weather patterns in the north of WA.

II. Winter – Variable intensity rainfall related to westerly frontal systems associated with temperate rainfall patterns in the south of WA.

Frequency analysis of rainfall data is an important part of hydrological design procedures. Analysis of rainfall data from single stations is often unreliable and may not provide temporally or spatially consistent data to use for design purposes. Instead, a set of accurate, consistent intensity-frequency- duration (IFD) design rainfall data has been derived for the whole of Australia by the BoM (2017). The IFD design rainfall depth (mm) for the site per annual exceedance probability (AEP) 4 event is presented in Table 5.

xiv Table 5 IFD design rainfall depths (mm) for NLN site

Duration Design rainfall depth (mm) per AEP event

50% 20% 10% 5% 2% 1%

5 min 4.49 7.19 9.26 11.5 14.9 17.8

10 min 6.91 11.1 14.2 17.6 22.6 26.8

15 min 8.5 13.6 17.5 21.7 27.8 33

30 min 11.4 18.2 23.4 29.1 37.4 44.6

1 hour 14.5 23 29.7 36.9 47.7 57.1

2 hour 18 28.5 36.7 45.6 59 70.6

3 hour 20.4 32.3 41.5 51.5 66.4 79.3

6 hour 25.5 40.2 51.5 63.8 81.6 96.8

12 hour 32.1 50.5 64.6 79.8 101 119

24 hour 39.8 63 80.6 99.7 126 148

48 hour 47.6 75.8 97.5 121 154 182

72 hour 51.3 82.1 106 132 170 202

Acknowledging the arid climatic setting of the TSF, conservative design criteria have been adopted for design. This provides for capacity for the TSF to withstand severe weather conditions such as high intensity, short-duration rainfall events that may cause erosion and other control failures, as well as high temperatures, low humidity and extended dry periods, which may result in poor vegetation establishment. 4.2 Hydrology

To support the surface water risk assessment, design rainfall intensity (mm/h) and rainfall depth (mm) have been calculated for the NLN catchments based on the BoM 2013 intensity-frequency-duration (IFD) curves. The IFD curves cover a range of AEP events from 50% to 1% and are shown in Figure 4.

IFD Design Rainfall Intensity IFD Design Rainfall Depth

1000 1000 - 50% - 50% - 20% - 20% ~ -10% ~ 100 E 100 E jl !. - 5% !. .l:'.. - 2% -s ..C - 1% ! I .5 j? 10 ,.~ 10 ·;.C a: a:

1 -1- l 4---1- 0.0 0.1 1.0 10.0 100.0 0.0 0.1 1.0 10.0 100.0 Duration (hour) Duration {hour)

Figure 4 IFD curves for rainfall intensity and rainfall depth used in design

xv Probable maximum precipitation (PMP)5 depths have been estimated using the BoM ‘Generalised Short Duration Method’, while design rainfall values for AEP events of between 1% AEP (1:100-year) and a PMP event (AEP of 1 × 10-5 %) were derived by using the interpolation procedure (Australian Rainfall and Runoff, Pilgrim et al, 1987). Figure 5 presents the rainfall depths for a number of average recurrence intervals (ARI) and storm durations for the NLN site.

RllOO --0.SOHour --0.75 Hour

]00.0 --1.00 Ho1.1r --2.00 Hour --3.CXJ Hoor --4.00 Hour

600.0

-e 500.0 s .r. 400.0 -0f ii i "'" 300.0

100.0 - ~

0.0 10 100 1,000 10,000 100,000 1,000,000 10,000,000 A.RI [years)

Figure 5 Intermediate rainfall depths for 2% AEP to PMP 4.3 Hydrogeology and groundwater

The hydrogeological unit underlying the TSF site is poor to moderate yielding, within deep fractured bedrock, or the weathered profile described above. This unit does not represent a major hydrogeological unit due to its interpreted low effective porosity and permeability.

The weathered rocks show a rapid decline in permeability with depth. Groundwater flows within this unit will only occur within local permeable faults/fracture zones, but these zones are not considered to be extensive. The inferred regional-scale flow direction for the current groundwater conditions is northwards from TSF Cell F. The depth to groundwater varies greatly due to mounding beneath the existing TSFs, generally ranging between 5 m to 14 m below ground level (bgl), depending on the proximity of monitoring bores to the TSFs.

Current groundwater levels in the vicinity of the TSFs are close to 520 m Australian Height Datum (AHD) due to this localised mounding beneath the TSFs. Prior to mining, the groundwater level was ~480 m AHD.

Current groundwater levels around TSF 3 are deeper along the western flank and shallow along the eastern flank, probably due to mine dewatering activity. There is an area of relatively shallow groundwater to the north of TSF 3 where TSF Cell F is to be located, which is attributed to seepage from the existing TSFs which migrates to the north.

Groundwater quality results indicate current nickel concentrations in the groundwater is in the sub- milligram per litre range, except for a few bores along the southern toe of TSF 2, which showed elevated nickel concentrations. Trace elements, other than nickel, show concentrations that are very

xvi low, or undetectable, and no trends are evident. Groundwater salinity, measured in terms of electrical conductivity (EC), remains similar to that measured during the 1990s. 4.4 Landforms and soil types

NLN is located within the eastern margin of the Agnew-Wiluna greenstone belt, which is made up of a complex of Archaean metamorphosed volcanic, intrusive and sedimentary rocks. The stratigraphic sequence of host rocks comprises a lower tholeiitic basalt with minor gabbro. This is overlain by a thick sequence of dominantly felsic, volcanic and volcanoclastic rock with minor mafics, chert and other sediments (including a carbonaceous shale). The ultramafic units have been altered and are generally serpentinised with varying degrees of talc-and carbonate alteration associated with ore mineralisation.

A widespread surficial high iron duricrust has formed below thin soils across the TSF site in variable thicknesses and durability. The duricrust overlies weathered volcanic rocks. The weathered profile occurs to depths of more than 60 m. 4.5 Flora and vegetation

Western Botanical have assessed the flora and vegetation of this region on several occasions in the past. The Initial flora and vegetation mapping was conducted in 1996, (Cockerton & Stratford, 1996), noting Calytrix uncinata occurring in this area. At that time, C. uncinata was listed as a Priority 3 taxon. Western Botanical assessed this area again in 2007 during flora and Vegetation surveys for the Rocky’s Reward cutback (Western Botanical, 2007), confirming the occurrence of C. uncinata. Subsequently, Calytrix uncinata has been removed from the Priority Flora list (DBCA, Florabase, June 2019). In 2017, Western Botanical undertook a Detailed Survey of the Camelot prospect, which included the area covered by the proposed G36/50 lease.

The proposed TSF Cell F lies within the Brooking Land System which is described as ‘Hills and ranges with Acacia shrublands, prominent ridges of banded iron formation supporting Mulga shrublands, occasional minor halophytic communities in the south east’, Pringle et al, 1994, refer Appendix E. In the Leinster – Mt Keith region, the Brooking Land System is associated with the Keith-Kilkenny Fault extending from south of Leinster to north of Mount Keith, some 120 km in extent.

The Study Area is within the Lateritic Mulga Wanderrie Shrublands with grassy understorey (LMWS) community and is located downslope of the adjacent Stony Ironstone Mulga Shrublands (SIMS) community to the west, refer Appendix E.

These are described as:

SIMS: The Stony Ironstone Mulga Shrubland habitat unit occurs on ironstone, quartz and chert ridges and associated slopes. The substrate is a dark red sandy loam with abundant subangular course fragments ranging in size from large stones on upper slopes to fine gravel on lower slopes. Vegetation is dominated by Acacia aneura sens. lat. Scrub over Eremophila latrobei subsp. latrobei, Scaevola spinescens Open Low Scrub over Ptilotus schwartzii var. schwartzii, Ptilotus obovatus var. obovatus Open Dwarf Scrub. This community is extensive and well represented to the west of the TSF Cell F and more broadly between Leinster and Mt Keith to the north.

LMWS: LMWS represents the lower foot slope and outwash plains of SIMS hills and supports Acacia aneura sens. lat. Low Open Woodland with an understorey typically consisting of Ptilotus schwartzii var. schwartzii, Ptilotus obovatus var. obovatus Open Dwarf Scrub and perennial grasses dominated by Monachather paradoxus, Thyridolepis multiculmis, occasional Eragrostis eriopoda.

Both these communities and their component species are widespread and abundant in the local area.

Results of three historical surveys have shown that no species with conservation listing, i.e. no Priority Flora and no Threatened Flora occur within the footprint of TSF Cell F. Priority Flora known in relatively close proximity (1 km radius) include Thryptomene sp. Leinster (B.L. Lepschi & L.A. Craven

xvii 4362) P3, Thryptomene nealensis P3, and Calytrix erosipetala P3. However, none of these will be directly impacted by the construction of TSF Cell F.

In late 2017, Western Botanical undertook a desktop assessment of significant flora in the Leinster region for the studies supporting the Camelot prospect development (Western Botanical 2017). The results of this desktop assessment identified a range of conservation significant flora in the region near Leinster, none of which occur within TSF Cell F.

There are no known Priority Ecological Communities or Threatened Ecological Communities in proximity to TSF Cell F. The closest vegetation related PEC known to the TSF Cell F is the Violet Range (Perseverance Greenstone Belt) vegetation complexes (banded ironstone formation) Priority 1 PEC, the south-eastern edge of which is some 17.7 km north-north-west and on the northern side of Lake Miranda. 4.6 Social environment

The land use of the surrounding region is pastoral and mining. Previous pastoral activity has caused land degradation in the region due to clearing and grazing. This has led to extensive vegetation loss and severe erosion in some areas. The TSF Cell F area is located within Albion Downs pastoral station, which is leased by NiW and its subsidiaries and subleased to a third party.

TSF Cell F is located at the Leinster mine site approximately 14 km north of the Leinster Town site. Given that TSF Cell F is in keeping with the existing landforms at the Leinster operations and has no sensitive adjoining land uses, it is unlikely to have a significant impact to visual amenity. 4.6.1 Aboriginal and European heritage

The Tjiwarl people are the native title holders (determined in April 2017) over approximately 13,000 square kilometres of land in the Northern Goldfields region of WA, with NiW operations at Leinster, Cliffs and Mt Keith are in the determination area.

NiW and the Tjiwarl Aboriginal Corporation, on behalf of the Tjiwarl people, have entered into a Comprehensive Agreement and an Indigenous Land Use Agreement (ILUA). The ILUA was registered on the Register of the Indigenous Land Use Agreements on 8 January 2019 (NNTT number WI2018/014). The Agreement area covers the Proposal area.

The NLN area, including the area required for TSF Cell F, has been archaeologically and ethnographically surveyed to identify Aboriginal heritage sites and, where practicable, these sites have been avoided through design, planning and engineering solutions. The proposed TSF Cell F does not impact any identified Aboriginal heritage sites.

xviii 5. Emissions and Discharges

5.1 Dust

Dust generated through the construction of the TSF Cell F will be managed through the implementation of water sprays, maintaining a wet condition for work surfaces and the use of water cart on access roads as required. 5.2 Waste management

The TSF Cell F will capture the tailings waste stream associated with the nickel processing facilities at Leinster. TSF Cell F is an extension of the existing tailings facilities currently in operation.

Any wastes generated as part of the construction process, including packaging etc, will be captured and disposed of at an appropriate landfill facility. All topsoil will be stockpiled and reused for landscaping / rehabilitation where practical. 5.3 Water management 5.3.1 Stormwater diversion

Surface water drainage systems around the NLN area and local drainage systems surrounding the proposed TSF development site, including contributing upstream catchments and drainage lines, are shown in Figure 6 and Figure 7.

---- -

Figure 6 Drainage lines at TSF Cell F

xix LEGEND

--CATCHMENT DRAI NAGE LINES D CATCHMENT AREAS D STAGE-1AEXTENT STAGE-18 & FINAL EXTENT DRAINAGE INFRASTRUCTURE - Existing Drainage Channel Proposed Sund

---- .. "'. Figure 7 Hydrological overview of TSF Cell F

An existing stormwater diversion channel runs along the eastern side of the existing TSF 3 cells, south of the proposed TSF Cell F location. The diversion channel currently captures upstream surface water flows from catchments to the east of the site and conveys water northwards, towards the northern drainage line in the vicinity of the proposed TSF Cell F development. It is proposed that this channel is extended further northwards. Runoff from the west of TSF Cell F will require short-term diversion until the area is in-filled with mine waste material.

Appendix C, Figure F010 shows the details of the stormwater diversion channels. Figure 6 indicates the temporary bund that will be constructed across the basin at Stage 1A to divert stormwater runoff from entering the TSF Cell F basin.

xx 5.3.2 Discharge

There will no discharge to surface waters from TSF Cell F. A water balance assessment for TSF Cell F has been developed (refer Appendix D, Section 7.8) taking into consideration typical inflows and outflows during operation of the facility including:

· Inflows – process water and incident rainfall

· Losses – interstitial, seepage and evaporation

· Return – recovered supernatant and rain water

In accordance with ANCOLD and DMIRS guidelines, the TSF has been designed with a minimum total freeboard of 500 mm above inflow from the 1:100 AEP 72-hour rainfall event during operation to contain the design rainfall event, without risk of overtopping.

The seepage interception and decant systems, as detailed in Sections 3.1.3 and 3.1.4 respectively, will ensure that no discharges to surface waters occur. 5.4 Groundwater

The existing TSF 3 Cells (A-E) and the proposed TSF Cell F lie above variably weathered and fractured Archaean granitoid/gneissic rocks and residual clays. Interpretations of the results of geophysics surveys and other mapping suggest that preferential flow paths occur within fractured/faulted hydrogeological units that tend to be of limited length, typically following a north-south alignment and hundreds of metres in length. These units are not generally considered to be ‘aquifers’ due to inherent low permeabilities and limited extents of the preferential pathways. The only aquifers of significance in the region are palaeochannel aquifers located approximately 15 km to the north and south of TSF 3.

Seepage of tailings porewater from TSF 3 has resulted in variable rates of rise in underlying groundwater levels (primarily to the north), with higher rates of rise occurring within the fractured/faulted pathways. While potential pathways exist to the west and east of TSF 3, monitoring demonstrates that seepage along these pathways is very limited due to hydraulic constraints imposed by the low permeability Perseverance Fault to the west and elevated topography and groundwater levels to the east.

Groundwater around the TSFs show little or no correlation with annual rainfall deficits, with groundwater levels mainly driven by operational factors. Groundwater levels immediately around TSF 3 have risen around 20 m since tailings deposition commenced in 1992, on average at a rate of around 0.8 m/year. The most recent groundwater level data (June 2018) indicate that groundwater levels have risen to within 5.28 m of ground surface at a distance of 400 m north of TSF 3AB, 600 m south of the northern limit of TSF Cell F. It has been shown previously that groundwater quality changes due to seepage are mostly related to potential rises in salinity (total dissolved solids concentrations) (Golders 20191). Changes in trace metal concentrations (e.g. nickel) are generally not observed due to the attenuation processes within the hydrogeological units.

Proposed tailings deposition at TSF Cell F will result in seepage to groundwater in an area that has already been affected by seepage. Rates of seepage will be lower than that which occurred historically during tailings deposition in the three cells of TSF 3, since the design of TSF Cell F incorporates an underdrain and so it is expected that seepage will mostly be collected and returned to the process water circuit. Nonetheless, seepage will affect groundwater conditions to the north of TSF Cell F, potentially posing a risk to water receptors to the north.

The nearest water receptor of ‘seepage-affected groundwater’ is ‘McArthurs bore’ located approximately 4 km north of TSF 3AB (Johnson, 1999). The risk of a negative impact to groundwater quality at this bore is considered low to negligible due to the substantial distance of the bore from TSF

xxi Cell F and given that fault/fracture (preferential) pathways tend to be limited in length, i.e. hundreds of metres rather than kilometres in length1.

It is proposed that four groundwater monitoring wells are established to the north and two to the east of TSF Cell F to permit ongoing monitoring of groundwater levels and quality, providing early warning of potential seepage impacts. Monitoring and reporting will be conducted in accordance with the licence L4612/1989/11.

1 Golders 2019, Leinster Nickel Mine Tailings Storage Facility Cell F, Design Report in Support of Mining Proposal and Works Approval Application June 2019 1788205-307-R-Rev2 xxii 6. Risk assessment

A risk assessment of the proposal covering all works, commissioning and operation was undertaken in accordance with DWER Guidance on Risk Assessments. Potential environmental risks associated with the project are summarised in Table 6.

NiW considers that with the existing and proposed management controls, the residual environmental risks associated with the project are deemed to be acceptable.

xxiii Table 6: Risk Assessment

Risk identification Risk Analysis (Prior to management / Risk Management Residual Risk Analysis (After Detailed Risk control measure) – refer to DWER management / control measure) – refer to Assessment Tables 1 and 2 DWER Tables 1 and 2 Required? Risk Possible Environmental Consequence Likelihood Risk Management / Consequence Likelihood Risk Matrix Result receptors and Matrix Control Measures Rating exposure Rating pathways Dust Airborne dust Soil and vegetation Slight Likely Medium · Water sprays and Slight Possible Low No – typical emissions (deposition) wet condition of construction activity / during work surfaces; impacts, proposed construction Human health water cart on controls considered activities (inhalation) access roads sufficient to address potential impact.

Hydrocarbon Hydrocarbon Soils (direct Minor Possible Medium · Immediate removal Slight Unlikely Low No – proposed spills from contamination contact) of spilled material; controls considered contractor contaminated sufficient to address plant and Surface Water material disposed potential impact equipment (runoff) of to an approved during location. construction Groundwater (infiltration) Surface Sediment Surface water Minor Unlikely Medium · Surface water Minor Rare Low No – proposed diversion or laden water (direct discharge) diversion in place controls considered dewatering discharges to (Golders Design sufficient to address discharge to local drainage Report 1788205- potential impact environment 037-R-Rev2 (July 2019)) · Dewatering if required, with discharge to TSF Return water pond Seepage Groundwater Groundwater Moderate Possible Medium · NiW Tailings Moderate Possible Medium No – commissioning from contamination (infiltration) Management and operation of TSF completed from tailings Master Plan Parts cells following TSF once in leachate 1-9 (submitted to completion of raise, operation seepage DWER February will be regulated 2019, as part of under Licence Works Approval L4612/1989/11 (to be application for raise amended to incorporate Cell F and

xxiv Risk identification Risk Analysis (Prior to management / Risk Management Residual Risk Analysis (After Detailed Risk control measure) – refer to DWER management / control measure) – refer to Assessment Tables 1 and 2 DWER Tables 1 and 2 Required? Risk Possible Environmental Consequence Likelihood Risk Management / Consequence Likelihood Risk Matrix Result receptors and Matrix Control Measures Rating exposure Rating pathways to Cell E, associated monitoring W6220/2019/1). bores). · Groundwater monitoring in accordance with existing Licence L4612/1989/11

Disturbance Loss of native Vegetation Moderate Unlikely Low · Clearing will be Minor Rare Low No – Clearing will be to native vegetation (clearing) conducted in conducted in vegetation outside accordance with accordance with the approved the requirements requirements of CPS clearing of CPS 8008/2 and 8008/2 and CPS footprint CPS 2222/4 2222/4

Disturbance Damage or Landforms Moderate Unlikely Medium · NiW internal Moderate Rare Medium No – no heritage sites to Aboriginal loss to (damage by mining Environment and identified within the Heritage Aboriginal equipment/vehicles) Heritage Impact proposed TSF Cell F heritage sites assessment footprint. process; (which requires checking of heritage survey GIS data prior to ground disturbance activities) Noise from Noise Human health Slight Rare Low · No nearby Slight Rare Low No – no nearby construction impacts to (noise) sensitive receptors sensitive receptors. activities nearby (located > 5km + (Occupational sensitive from mine site) exposure not receptors considered in this assessment).

Failure of Uncontrolled Land (direct Severe Unlikely High · Design and Severe Rare High Detailed risk tailings tailings discharge) construct in assessments were storage cells discharge to Surface water accordance with conducted as part of the (direct discharge) recognised industry the design process, environment Human health guidelines and refer: (direct impact) internal standards. · Appendix D, Section 7 Golders Design

xxv Risk identification Risk Analysis (Prior to management / Risk Management Residual Risk Analysis (After Detailed Risk control measure) – refer to DWER management / control measure) – refer to Assessment Tables 1 and 2 DWER Tables 1 and 2 Required? Risk Possible Environmental Consequence Likelihood Risk Management / Consequence Likelihood Risk Matrix Result receptors and Matrix Control Measures Rating exposure Rating pathways · Construction in Report 1788205- accordance to 037-R-Rev2 (July Golders Design 2019) Report 1788205- · TSF Cell F Design 037-R-Rev2 (July Third Party Review 2019) 754-PERGE229998 · Annual operational (June 2019) and safety reviews by independent experts · Buttressing of external walls of Leinster TSFs to maintain / exceed safety factors · NiW Tailings Management Master Plan · TSF Cell F Design third Party Review (Coffey 2019)

xxvi Table 1 - Risk Criteria Table

Consequence L1kellhood

Tho followmg cr1tena wlll b• used to determine the consequences of a nsk event ocwrrlng The followlng cntena will be used to dltermme the likelihood of the nsk event occurnng

Environment Public Health* and Amanl ty (such as air • nd water quality, noise, and odour)

Severe on-site impacts: c:atastrophic Lossc:Alife Almost The nSk. evenl iS expected to occu- in most Certain e,cunstances off-site impacts local scale: high level or abo\le Adversa health effects: high level or ongoi'lgmedical off-site impacts wider scale: mid level orabove ""atme"' Speck Consequence Critena (for pubic health)are Mid to long tern, orpennanent impact to an area olhigh significantly exceeded conservation value°' spedal significance" Local scale impacts: permanent loss a-nerity Specific Consequence Crkeria (bf e11V1ronment) are ot significantty exceeded

Major on-site impacts: high level Adverse health effects: mid level or ~tmedical Likely The riSk event wil probably occur In most c:ita.mstances off-site impacts local scale: mid level treatment Specl'lc Consequence Crw.eria (tor public health) are exceeded off-site impacts w ider scale: IOwlevel Local scale impacts: high level impact 1oameoity Short tern, impact to an area of higt'I conseivation value or spedajsignificanoeA Spedfic Consequence Cderia (bf envuorvnent) are e,ceed,d

Moderate on-site impacts: mid level AdYerMt health effects: loWlevel orocx:aslOl'lalmedical PosSible treatment off-site impacts local scale: lowlevel off-site impacts wider scale: minimal Speck Consequence Criteria (for public health) ate at nskof not being met Specific Consequence Cderia (for el'IVlrorwnent) are at risk d Local scale impacts: rrvd levet i11pact toamenrty not being met

Minor on-site impacts: lowlevel Specl\c Consequence Criteria (for public health)are ld(ety tobe Unlikely The risk event wil probably not oc:::cur n met mostcirOJmstanc:es. off-site impacts local scale: minimal Local scale impacts: low level impact to amenity off-site impacts wider scale: notdetectab6e Specific Consequence Cderia (for environment) likely to be met

Slight on-site impact: ITlll"limal Local sea.le: minimal impacts to.wnenrty ..,, The nSk evert may only oc:::cur., exceptional cn::unstances Specific Consequence Crleria (tor envirorvnent) met Speeh:Consequeooe Criteria (for public health)criteriamet

,.. Determination of areas of high conservation value or special significance should be informed by the Guidance Statement: EmAronmental Sffing • In applying public health criteria, DER may have regard to the Department of Health's, Health Rjsk Assessment (Scoping) Guidelines ..on •site" means within the prescribed premises boundary

Table 2 - Risk Rating Matrix

Likelihood Consequence

Slight Minor Almo.t Certain Medium

Likely Medium Medium

Poulble Low - Unlikely Medium Medium Low - Rare Low Low Medium Medium

Reference: DWER, Guidance Statement: Risk Assessments Part V, Division 3, Environmental Protection Act 1986, Feb 2017

xxvii 6.1 Environmental Management of TSFs

NiW operates the Leinster Tailings Storage Facilities (TSF) in accordance with the BHP NiW Leinster Nickel Operation Tailings Management Master Plan (TMMP) which consists of the following parts: · Part 1 Description of Existing Facilities · Part 2 TSF Operating Manual · Part 3 TSF Water management plan · Part 4 TSF Monitoring Plan · Part 5 TSF Licensing Plan · Part 6 TSF Risk Management Plan · Part 7 TSF Decommissioning and Closure Plan · Part 8 TSF Emergency Procedures Management Plan · Part 9 TSF Roles and Responsibilities

Copies of these documents have been provided to DWER as part of the assessment of Works Approval W6220/2019/1 for the 2019 upstream raise of TSF 3 Cell E, and are held on DWER records.

In addition, the TSF Emergency Response Plan Procedure (NLN HSEC PRO 244) is in place to guide actions in the event of catastrophic failure of the Leinster TSF from overtopping failure, seismic failure or static failure.

The TMMP documents, whilst reflecting current practice, are currently under review and revision to bring information (such as role titles, Government agency title changes etc) up to date. The current TMMP documents remain in force until these revisions are completed.

The design and maintenance of all new and existing TSF’s are subject to BHP’s internal Water and Tailings Storage Facilities Our Requirements (30 May 2019).

NiW undertakes annual audits of all TSFs using an independent geotechnical specialist, as required by the Department of Mines, Industry Regulation and Safety (DMIRS).

Table 7 provides further information regarding controls in place for the safe construction and operation of NiW’s tailings storage facilities.

Table 7: NiW TSF Design and Construction Information

Item Requirements Specifications (including Rationale NiW Management # professional accreditation requirements) 1 Independent review Undertaken by a suitably The primary control TSF Cell F designed in of the design, qualified engineer or mechanism to prevent, accordance with Australian construction and geotechnical specialist in control and mitigate and international standards, operation of TSF cells accordance with the impacts to the refer Appendix D relevant parts of Australian environment from the National Committee of embankment raise is Independent third party Large Dams (ANCOLD) the structural integrity review of design (May 2012), of the TSF as a whole Guidelines on tailings structure, including NiW undertakes regular dam Dams – Planning, design, foundations and the safety reviews following Construction, Operation current embankment construction. Further details and Closure; and DMIRS raise. are provided in the TMMP (2017) Tailings storage Part 1 - Description of facility audit – guide. Existing Facilities

2 Updated Tailings In accordance with the Although the Seepage management is Storage relevant parts DMIRS construction and described in the TMMP Part Facility Management (2017) Tailings storage design are critical to the 2 Operating Manual and TSF Plan facility audit – guide; and structural integrity of Cell Design Report and/or Operating Department of Mines and the embankments, (Appendix D, Section 7.6) Strategy that Petroleum (August 2015) other factors may xxviii Item Requirements Specifications (including Rationale NiW Management # professional accreditation requirements) includes: Guide to Departmental influence stability – The active TSF cells at - A Seepage requirements for the such as the size and Leinster are paddock type management plan; management and closure extent of the saturation cells, operated with - Measures for of tailings storage facilities zone within the TSF, perimeter deposition, with controlling (TSFs). seepage management supernatant ponds located deposition and practices, tailings around the central decant ponding within the deposition, decant structures, away from TSF recovery perimeter embankments to maintain stability of these embankments. Decant water is gravity drained via pond underdrainage to an HDPE lined decant pond, where the water is returned to the Leinster processing circuit. 3 Updated Tailings In accordance with the Surface water runoff The TSF Cell F Design Storage relevant parts of ANCOLD and flood events that Report (Appendix D) Facility Management (May 2012), Guidelines on inundate the base of - Consideration of Dam Plan tailings Dams – Planning, the TSF have the ability break assessment for Cell and/or Operating design, Construction, to compromise the F (Section 7.5). Strategy That Operation and Closure; embankments. In the includes: and Department of Mines, event of an Refer to: - A dam break study Industry Regulation and embankment failure or - TMMP Part 8 TSF for the new TSF Lift safety (Tailings storage ‘dam break’ event, Emergency Procedures and a water facility audit – Guide.2017) incident impacts are Management Plan; and balance likely to be significant - TSF Emergency Response demonstrating with lasting impacts Procedure (in the event of capacity to contain spread over a large catastrophic failure). incidental rainfall geographical area. from a 72 hour 1:100-year Annual Recurrence Interval rainfall event. - An Emergency Response Plan and Trigger Action Response Plan for the TSF 3E

7. Fee calculation

The cost of construction of TSF Cell F is outlined in Table 8

Table 8 TSF Cell F Construction Costs

Development Stage Cost ($) Stage 1A and 1B Earthworks and site establishment 3,257,000 Decant and drainage systems 751,000 Ancillary items 623,000 Lifts 1 – 7 Earthworks and site establishment 974,000 Decant and drainage system upgrades 13,000 Ancillary items 348,000 Total cost of TSF Cell F Stage 1A, 1B and Lifts 1-7 $5,966,000

Based on the above costing and in accordance with section 12.6 of the Application for Works Approval Form, the application fee has been calculated as $12 383, refer Table 9. xxix Table 9: Fee calculation

Estimated Cost Works Approval Fee Calculation of works $ Fee Units1 Fee Unit = $40.602 $ 5,966,000 305 40.60 x 305 = $12,383.00

1 Schedule 3, Environmental Protection Regulations 1987 [as shown below] 2 2018-19 Fee schedule, https://www.der.wa.gov.au/our-work/licences-and-works-approvals/489-industry-regulation-faqs

Environmental Protection Regulations 1987 Schedule 3 Works approval fee

Schedule 3 - Works approval fee [r. SBA(!)] [Heading amended: Gazelle 12 Jun 2018 p. 1889.) Cost of works Fee units Not more than $IO 000 15 More than $IO 000 but not more than 15 plus 5 for every $IO 000 above $50 000 $ 10 000 More than $50 000 but not more than 35 plus IO for every $50 000 above $500 000 $50 000 More than $500 000 but not more than 125 plus 20 for every $500 000 $5 000 000 above $500 000 More than $5 000 000 but not more than 305 plus 100 for every $5 000 000 $25 000 000 above $5 000 000 More than $25 000 000 but not more 705 plus 50 for every $5 000 000 than $ I 00 000 000 above $25 000 000 More than $ I 00 000 000 1405

xxx