SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Surface Water Studies North Star Magnetite Project Final Report
301012-01539
Sep 2012
Level 7, QV1 Building 250 St Georges Terrace Perth WA 6000 Australia Tel: +61 8 9278 8111 Fax: +61 8 9278 8110 www.worleyparsons.com WorleyParsons Services Pty Ltd ABN 61 001 279 812 © Copyright 2012 WorleyParsons Services Pty Ltd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Disclaimer
This report has been prepared on behalf of and for the exclusive use of Fortescue Metals Group and is subject to and issued in accordance with the agreement between Fortescue Metals Group and Worley Parsons. WorleyParsons accepts no liability or responsibility whatsoever for it in respect of any use or reliance upon this report by any third party.
Copying this report without permission of Fortescue Metals Group or WorleyParsons is not permitted.
PROJECT - SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT REV DESCRIPTION ORIG REVIEW WORLEY- DATE CLIENT DATE PARSONS APPROVAL APPROVAL
1 Issued for use Aug 2012 Ian Varley B Stinton M Dowling
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SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
CONTENTS
1. INTRODUCTION ...... 1
2. NORTH STAR PROJECT DESCRIPTION ...... 2
3. REGIONAL CLIMATE AND CATCHMENTS ...... 4
3.1 Regional Rainfall ...... 4
3.2 Evaporation ...... 5
3.3 Regional Stream flows and Flooding ...... 6
3.4 Climate Change ...... 10
4. NORTHSTAR PROJECT AREA SURFACE WATER CHARACTERISATION ...... 14
4.1 Sub Catchments ...... 14
4.2 Design Rainfalls ...... 14
4.3 Design Flows ...... 15
4.4 Vegetation and Land Systems ...... 16
4.5 Ecology ...... 18
5. PREDICTED HYDROLOGICAL CHANGE DUE TO NORTHSTAR ...... 20
6. REFERENCES: ...... 28
FIGURES ...... 29
APPENDIX 1: VEGETATION ASSOCIATIONS ...... 37
APPENDIX 2: LAND SYSTEMS WITHIN THE NORTH STAR PROJECT AREA ...... 39
APPENDIX 3: IDENTIFICATION OF ENVIRONMENTAL FACTORS ...... 41
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1. INTRODUCTION
FMG Iron Bridge Ltd, a subsidiary of Fortescue Metals Group Ltd is planning the development of the North Star iron ore Magnetite mine in the Pilbara, which is located approximately 100km south of Port Hedland, on the boundary between the Turner River and Shaw River catchments. Further references to ‘Fortescue’ refer to both FMG Iron Bridge Ltd and Fortescue Metal Group Ltd.
WorleyParsons were engaged to undertake a high level desktop study to characterise the natural hydrologic regime of the catchments in which North Star development is to be located and to assess the change in the regime due to the development of the mine.
The scope of this work includes:
• Regional surface water characterisation:
o Identify regional catchments in which the mine and access road is proposed.
o Describe the regional climate.
o Describe any surface water dependent ecosystems in the vicinity of the development, particularly those that are threatened or are considered to be regionally significant.
o Describe the hydrologic regime of the regional catchments (including climate, stream flows if recorded, regional flood levels).
o Provide advice on climate change.
• North Star project area surface water characterisation:
o Delineate sub catchments within the proposed project area (mine and haul road)
o Describe sub catchments and land use pre development.
o Map land use, soils and vegetation.
o Provide information on recorded rainfalls and stream flows if available for the sub catchments.
o Provide design rainfalls and design flows for the sub catchments.
o Describe changes to design flows.
o Describe any hydrologic features of environmental relevance, including sheet flow areas and pools/wetlands that have been identified within these sub catchments.
o Describe changes to the hydrologic regime within, and downstream of the sub catchments and at any pools or sheet flow areas that have been identified.
o Comment on the change to the regional hydrologic regime as a result of the proposed development.
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2. NORTH STAR PROJECT DESCRIPTION
Fortescue proposes to develop a new iron ore mine approximately 110km south of Port Hedland, known as the North Star Magnetite Project (Project). The Project includes a new mine with one mine pit, one waste rock dump (WRD), one tailings storage facility (TSF), one low grade ore stockpile (LGOS), crushing and screening hub, magnetic separation processing plant, roads, and other associated mine infrastructure. The Project is premised on a maximum of 30 Million tonnes per annum (Mtpa) Run of Mine (ROM) feed of magnetite ore with a mine life of 45 years. The ore will undergo crushing and screening, then magnetic separation, with up to 15 Mtpa of product being sent to Port Hedland for export as concentrate. The key characteristics of the Project are summarised in Table 1.
Table 1: Key Characteristics of Proposal
Relevant Characteristics Description Iron ore mining, crushing, grinding and magnetic separation, Main Activities transport of magnetite concentrate by slurry pipeline to Port Hedland for dewatering and stockpiling. Resource Up to 2.1 Billion tonnes of magnetite. Total Material Moved Up to 2,500Mt at maximum mining rate of 155Mtpa. Tailings Up to 540Mt of tailings Life of Mine Approximately 45 years. Total Disturbance Footprint Approximately 5000 hectares. Pit Size 4.5 km in length, 1km in width. Pit Depth Maximum depth of 375m below original ground level Standard open cut mining proposed. Overburden and waste material will be permanently placed outside of the open pit mining area in a Mining Method dedicated landform. The opportunity for backfill of the pit will be reviewed during mining operations. Waste/Overburden Volume Approximately 913Mt of hard rock and 180 Mt of dry process rejects. Approximately 3Mt to be stored in a temporary stockpile, no more Topsoil Volume than 2m high for use in rehabilitation. Export Tonnage Up to 15Mtpa. Minimal dewatering will be required from the open pit due to the Dewatering Requirements limited available water within the host rock. An estimated dewatering rate of 0.5Glpa has been calculated. Mine Site Infrastructure and Ancillary Services Processing of magnetite will involve primary and secondary crushing Ore Processing and grinding. Product separation will be through a combination of low intensity magnetic and dry air classification. Power 110MW to be built at the mine site. Up to 4,000 kL stored within a dedicated fuel farm and satellite tanks Fuel Storage Requirements for major fuel use areas
Construction: 2.5GLpa supplied by bores located within Fortescue’s Water rail corridor
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Operations: up to 14GLpa supplied by bores located at the Canning Basin. Workshops and Administration Administrative and maintenance buildings; Product stockpiles and Facilities workshops, fuel storage and explosive storage magazine.
Camp Construction Camp of 2,000 beds Operations Camp of up to 800 beds Construction approximately 2,000 (drive in drive out from Port Hedland) Workforce Operational Approximately 800 (drive in drive out from Port Hedland) Operational hours are 24hrs per day, 7 days per week. A 600mm buried steel pipeline will be used to transport magnetite Transport concentrate as slurry from site to Pt Hedland for filtering and stockpiling prior to shipping.
The total area of disturbance associated with the Project is approximately 5,000 ha1. The ore mining methodology employed for the Project will involve conventional drill and blast, followed by hydraulic excavation and haulage to processing facilities and stockpiles by off road haul trucks.
The Project involves the development of a single Mine Pit which will be approximately 4.5km in length and 1km in width. Minimal mine pit dewatering will be required. In-pit sumps may be required to collect any incidental rainfall or seepage during mining activities with sub-surface drainage from the surrounding country rockinto the ore body. It is proposed to construct a levee bank around the Mine Infrastructure area to provide flood protection for a 1 in 100 year Average Recurrence Interval (ARI).
Up to 913 Mt of waste rock (410 Million Loose Cubic Metres (MLCM)) will be mined throughout the life of the Project. A waste landform will be required with an approximate area of 991 ha to contain this volume of waste. The waste landform will be a maximum height of 340m AHD, which is the approximate height of the surrounding ridgelines (332m AHD).
Ore will be transported via haul trucks to the run-of-mine (ROM) facility, where it will be stockpiled prior to processing.
A 600mm buried steel pipeline will be used to transport magnetite concentrate as slurry from site to Port Hedland for filtering and stockpiling prior to shipping.
A 38.5 km access road to North Star will be constructed to connect to the Great Northern Highway. The access road will utilise 1.5km of the existing Wittenoom Road and existing level crossings at the BHPB Newman rail mainline. The access road will be suitable for Class 1, 2 or 3 Restricted Access Vehicles (RAV) traffic. A 20m wide constructed road pavement will be required to allow for access of heavy haulage trucks and light vehicles. The total disturbance width of the road will be 30m to allow for road berms, shoulders and drains. The access road basis of drainage design will satisfy a 1-in-5- year ARI rain event.
1 The disturbance area has been calculated to provide allowance for construction activities such as gaining access to the designed area and providing sufficient area for shaping and battering of designed slopes.
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3. REGIONAL CLIMATE AND CATCHMENTS
3.1 Regional Rainfall
The Pilbara region has a hot semi-arid to arid climate. Average annual rainfalls range from 300 mm to 350 mm within a 100 km radius of the North Star mine. The location of daily rainfall gauging stations in the study area is shown in Figure 1.
Rainfall occurs mainly in the three month period from January to March (refer to Chart 1) with major falls occurring from cyclone, tropical lows and convective thunder storms. Rainfall is highly variable with a mean annual rainfall of 300-360 mm, but annual totals vary from 0 mm to over 1000 mm. Relevant statistics for rainfalls stations in the Pilbara are presented in Table 2. Note that the closest long term rainfall gauge to the site is Wallareenya.
400 Monthly Rainfall - Wallareenya (004038) Max 350 75th Percentile 300 Median 25th Percentile 250 Min
200
150
Rainfall Rainfall (mm) 100
50
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month
Chart 1: Monthly Rainfall Statistics for Wallareenya
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Table 2: Annual Rainfall Statistics (based on a water year commencing 1st Oct) Mean Median Min Max 25th 75th Stand. Dist. to Years of # Annual Annual Annual Annual Percen- Percen- Dev. site record Rainfall Rainfall Rainfall Rainfall tile tile (km) Location (mm) (mm) (mm) (mm) Mallina 327 294 0 880 196 419 174 113 1901- (004059) 2008 Wallareenya 319 312 24 706 186 375 140 59 1909- (004038) 2011 Strelley 358 358 13 944 205 464 182 86 1907- (004036) 2011 Carlindie 316 302 48.3 994 202 400 167 70 1908- (004008) 2005 Marble Bar 361 315 168 706 250 446 169 74 2001- (004106) 2010 Indee 328 282 33 859 202 428 170 68 1909- (004016) 2007 Hillside 335 306 25 1268 206 393 197 66 1917- (004015) 2008 Redmont 312 304 54.2 553 212 399 124 84 1926- (004043) 1993 # Years of record available from Bureau of Meteorology website.
3.2 Evaporation
Evaporation rates in the Pilbara are very high with the mean annual potential evaporation being approximately 3,400 m (WRC 2000), or ten times higher than the mean annual rainfall. Evaporation rates vary seasonally with mean monthly evaporation rates ranging from 2.5 mm/day to 18 mm/day, refer to Chart 2.
Chart 2: Monthly Evaporation (From Surface Hydrology of the Pilbara Region, Water & Rivers Commission, Report No SWH 32 (WRC 2000))
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3.3 Regional Stream flows and Flooding
The North Star mine is located on the boundary between the Turner River and Shaw River catchments. Refer to Figure 1 for a regional locality map which shows the location of the mine and access road in relation to regional catchment areas. The mine layout is shown in Figure 2, key features include:
• The mine pit • One tailing storage facility to the north of the mine pit • A stockpile to the west of the pit • A waste rock dump to the east of the pit
The mine pit runs approximately along the boundary between the Turner River and Shaw River catchments, with the majority of the mine site located within the Turner River catchment. Sub- catchments potentially impacted by the mine are] shown in Figure 3. The footprint of the mine disturbance area is relatively small compared to the Turner River and Shaw River catchments, as can be seen from Table 3.
The proposed access road runs directly west from the mine site for a distance of approximately 20 km where it connects to an existing road/rail transport corridor. The access road runs alongside a tributary of the Turner River as well as crossing numerous minor waterways. The catchment areas for these crossings are shown in Figure 4.
The nearest stream flow gauging station to the North Star mine is on the Turner River at Pincunah, which was established in 1985 and has a catchment area of 885 km2. The next closest stream flow gauging stations are located on the Yule River at Kangan Homestead and the Shaw River at Upper North Pole. Refer to Figure 1 for the location of these gauging stations.
Table 3: Relative Catchment Areas Total Approx. Mine Percentage of Catchment Footprint in Mine Footprint Catchment Area Catchment in Catchment (km2) (km2) (%) Strelley River (sub-catchment of the Shaw R) 2805 10 0.36 Turner River 4802 40 0.83
Streams in the region are ephemeral and flow for only a short duration following rainfall events, typical for streams in the Pilbara. A plot of daily stream flows is provided in Chart 3 for the Turner River at Pincunah showing flows to be intermittent, generally occurring in the wet season (January-March) with long periods of no flow during the dry season. In years with low rainfall there are no flows.
Flow duration curves are provided in Chart 4 for the total period of record (26 years-1985 to 2011), as well as the wettest and driest years. The flow duration curve for the total period shows that flows only occur for 51 days per year and zero flows for 314 days. However, behaviour varies remarkably from
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SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT one year to the next. The driest year had 365 zero flow days whilst the wettest year had flow for 277 days.
Key hydrological statistics for the Turner River at Pincunah are provided in Table 4. These statistics characterise the natural flow regime and are found to be relevant for assessing impacts on ecosystems. The statistics show that in the 27 years of record there have been 64 significant flow events, or approximately 2 events per year. However, some years had no flow, whereas others had multiple flow events. The average duration of a flow event is approximately 12 days and the average flow rate during these events is 54m3/s. The mean annual flow volume is 33,250 ML, which corresponds to a mean runoff depth of 37 mm. Therefore, runoff represents approximately 10% of the mean annual rainfall.
Daily Streamflows for Turner River at Pincunah (709010) 60000.0
50000.0
40000.0
30000.0 Flows (ML/d) Flows 20000.0
10000.0
0.0
Date
Chart 3: Daily Flows for Turner River at Pincunah
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Flow Duration Curve - Turnet River at Pincunah (709010)
100,000.0
10,000.0
1,000.0
100.0 Flow (ML/d)
10.0
1.0 0 10 20 30 40 50 60 70 80 90 100 Exceedance (% of time)
FDC from all years FDC for wettest year FDC for driest year
Chart 4: Flow Duration Curve Turner River Flow Gauge
Table 4: Key Hydrologic Statistics for Turner River at Pincunah (based on daily flow volumes) General Statistics Whole Period Minimum daily flow (ML) Min 0 Maximum daily flow (ML) Max 54,171 Mean daily flow (ML) MDF 89.77 Median daily flow (ML) Med 0 CV CV 12.5 Standard Deviation STD 1,125 Skewness Skw Infinity Zero flow days Zer 7947 Zero flow days (%) Zer% 86 Days Less or equal 10 ML/d Under10 8224 Days Greater or equal 10 ML/d Greater10 1007 High Flow Spell result Whole Period High Spell Threshold (ML/d) HSThld 50 Number of High Spells HSNum 64 Mean of High Spell Peaks (ML/d) HSPeak 4676 Mean Duration of High Spells (days) HSMeanDur 11.5
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Low Flow Spell result Whole Period Low Spell Threshold (ML/d) LSThld 10 Number of Low Spell LSNum 48 Mean Duration of Low Spell (days) LSMeanDur 171 Moving Average & Julian Dates Whole Period Julian date MaxMean JDMaxMean 43 (mid February) Julian date MaxMed JDMaxMed 42 (mid February)
A flood frequency analysis was applied to the recorded flows (Turner River at Pincunah) in order to provide an estimate of the peak flood discharges for a range of annual Exceedance Probabilties (AEP’s). Since there were four years with zero flow the partial series was applied with a threshold flow of 110 m3/s. This gave 24 events, which equalled to the number of years of record. The 2 parameter Log Normal distribution was found to give the best fit to the data, refer to Chart 5. The estimated peak discharges are provided in Table 5. Peak discharges provided by the Flavell Regional Flood Frequency Procedure (RFFP) are also provided for comparison purposes. The RFFP method is based on flood frequency analysis of stream flow gauging stations across the entire Pilbara region and is typically used to estimate design flows. It can be seen that the RFFP gives higher values than frequency analysis of the Pincunah gauging station. This suggests that flood discharge rates from the Turner River catchment are lower than the average discharge rates for the Pilbara region. The 1 in 100 AEP flood extents in the vicinity of the mine and access road are provided in Figure 4. It can be seen that the access road is not located on the floodplain, but a portion of the mining footprint is within the mapped floodplain. Thus parts of the mining footprint will require diversion drains and flood protection levees.
Table 5: Estimated Peak Flood Discharges for Turner River at Pincunah Peak Flood Discharges (m3/s) AEP Flood Frequency Analysis# Flavell RFFP 1 in 10 785 1,050 1 in 20 1055 1,700 1 in 50 1472 3,180 1 in 100 1840 5,110 # Partial series flood frequency analysis with number of peaks equal to number of years of data (n=24). Threshold flow of 110 m3/s.
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Chart 5: Flood Frequency Analysis (Turner River at Pincunah – 1985 to 2011)
3.4 Climate Change
Examination of historical rainfall records shows that there is a slight trend for increasing rainfall in the North Star region of the Pilbara (refer to Chart 6). This is consistent with the results of a study by the Bureau of Meteorology for all of Australia, which showed that the Pilbara has experienced an increase in annual rainfall of between 1-5 mm/annum since 1970 (refer to Chart 7). In contrast to the observed trend, climate modelling by the CSIRO has estimated that mean annual rainfall in the Pilbara is likely to decrease slightly (by 2-10%) by the year 2030 (refer to Chart 8). The impacts of reduced rainfall will be exacerbated by a slight increase (1-1.5oC) in mean annual temperatures (refer to Chart 9), which is estimated to give a 2-4% increase in potential evapotranspiration (refer to Chart 10). Hence, given the resulting drier antecedent soil moisture, the decrease in surface water flows is likely to be more than the decrease in rainfall.
There still remains much uncertainty over the impact of global climate change on the patterns of precipitation in the Pilbara. There are also longer term climate cycles at play which remain poorly understood. While the observed and predicted trends may be considered significant in absolute terms, they are small in comparison to the annual variability in extremes that are characteristic of the
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SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT region (as illustrated in Chart 5). Management of such extremes will continue to be important for water management at mine sites in the Pilbara.
Annual Rainfalls with Trendline - Wallareenya-(004038) 800 700 600 500 400 300 200
AnnualRainfall (mm) 100 0 1900 1920 1940 1960 1980 2000 2020 Year
Chart 6: Annual Rainfalls at Wallareenya
Chart 7: Annual Rainfall Trends across Australia
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Chart 8: Predicted change in mean annual rainfall by year 2030 (Source http://www.climatechangeinaustralia.gov.au/watemp1.php)
Chart 9: Predicted change in mean annual temperature by year 2030 (Source http://www.climatechangeinaustralia.gov.au/watemp1.php)
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Chart 10: Predicted change in mean annual evapotranspiration by year 2030 (Source http://www.climatechangeinaustralia.gov.au/watemp1.php)
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4. NORTHSTAR PROJECT AREA SURFACE WATER CHARACTERISATION
4.1 Sub Catchments
A total of 9 sub-catchments have been identified at the mine site, refer to Figure 3. The majority of the catchments drain towards the Turner River, but runoff from the waste rock dump drains towards the Strelley River catchment. The catchments are hilly with slopes ranging from 2%-6%. The dominant vegetation is eucalyptus woodland and hummock grassland, refer to Figure 5.
4.2 Design Rainfalls
Design rainfall intensities for the mine site sub catchments were derived using the Bureau of Meteorology (BOM) online IFD calculator for the location of Latitude 21.250 Longitude 119.050. The design rainfall intensities and depths are provided in Table 6 and Chart 11. Whilst the Pilbara region experiences reasonably low annual rainfall totals, peak rainfall intensities during cyclone and thunderstorm events are relatively high. It is not uncommon for the majority of the rainfall for a given year to occur during one or two intense storm events. Table 6 shows that the rainfall during a 24 hour 1 in 100 Average Recurrence Interval (ARI) event is 300 mm, which approximates the mean annual rainfall.
Table 6: Design Rainfall Intensities (Intensities and depths shown) AEP DURATION 1 in 1 1 in 2 1 in 5 1 in 10 1 in 20 1 in 50 1 in 100 mm/hr mm mm/hr mm mm/hr mm mm/hr mm mm/hr mm mm/hr mm mm/hr mm
5 mins 80.1 6.7 107. 8.9 151. 12.6 179. 14.9 215. 17.9 264. 22.0 302. 25.2
6 mins 74.3 7.4 99.2 9.9 141. 14.1 167. 16.7 201. 20.1 247. 24.7 283. 28.3
10 mins 61.1 10.2 81.9 13.7 117. 19.5 140. 23.3 169. 28.2 209. 34.8 240. 40.0
20 mins 45.9 15.3 61.9 20.6 90.4 30.1 109. 36.3 132. 44.0 165. 55.0 191. 63.7
30 mins 37.6 18.8 50.9 25.5 75.1 37.6 91.0 45.5 111. 55.5 139. 69.5 161. 80.5
1 hour 24.8 24.8 33.8 33.8 50.8 50.8 62.2 62.2 76.6 76.6 96.7 96.7 113. 113.0
2 hours 15.0 30.0 20.6 41.2 31.6 63.2 39.2 78.4 48.6 97.2 62.1 124.2 73.0 146.0
3 hours 10.9 32.7 15.0 45.0 23.3 69.9 29.1 87.3 36.3 108.9 46.7 140.1 55.1 165.3
6 hours 6.17 37.0 8.57 51.4 13.6 81.6 17.2 103.2 21.7 130.2 28.1 168.6 33.5 201.0
12 hours 3.55 42.6 4.96 59.5 8.03 96.4 10.2 122.4 13.0 156.0 17.0 204.0 20.4 244.8
24 hours 2.10 50.4 2.96 71.0 4.84 116.2 6.19 148.6 7.90 189.6 10.4 249.6 12.5 300.0
48 hours 1.24 59.5 1.75 84.0 2.87 137.8 3.68 176.6 4.71 226.1 6.20 297.6 7.46 358.1
72 hours 0.87 62.6 1.22 87.8 2.01 144.7 2.58 185.8 3.31 238.3 4.38 315.4 5.28 380.2
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Chart 11: Rainfall Intensity Frequency Duration Curves for North Star Mine Site (Generated using the Bureau of Meteorology online IFD calculator)
4.3 Design Flows
Peak flows for the mine site catchments depicted in Figure 3 were estimated using the Regional Flood Frequency Procedure (RFFP) developed by Flavell (2005) and are presented in Table 7. This method was derived using stream-flow and rainfall data sets collected from gauged catchments in the Pilbara, which have areas ranging between 52 and 41,400 km2. Given that some of the mine site catchments are considerably smaller, the peak flows estimated by the RFFP may under estimate discharges (because of the lesser influence of storage, which reduces peak flows, in smaller catchments). It may therefore be more appropriate to apply other estimation procedures for the smaller catchments during detailed design of mine site drainage infrastructure such as road culverts, and diversion drains.
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Table 7: Estimated peak flood discharges for mine site catchments (using Flavell method) Area Catchment 2 AEP (km ) 1 in 10 1 in 20 1 in 50 1 in 100 M1 2.18 23 35 60 91 M2 3.71 40 61 106 162 M3 0.46 10 16 27 40 M4 1.69 30 46 79 120 M5 3.16 22 35 61 93 M6 1.34 12 17 30 45 M7 4.5 30 47 83 127 M8 20.5 105 163 291 453 TSF 19.7 102 189 339 528
4.4 Vegetation and Land Systems
Pre-European vegetation has been mapped at a broad scale (1:1,000,000) for the Pilbara region (Beard 1975, Department of Agriculture Western Australia 2005) and is shown in Figure 5 for the North Star project area. Descriptions of the vegetation categories are provided in Appendix 1. Three broad vegetation associations have been mapped within the access road and proposed mine site:
• The vegetation association ‘Eucalyptus camaldulensis woodland’. This association represents riparian vegetation and occurs on major drainage lines and coincides with the River land system.
• The vegetation association ‘Grevillea mixed sparse shrubland’. This association usually occurs on stony plains and low rolling hills.
• The vegetation association ‘Eucalyptus leucophloia open woodland and Triodia open hummock grassland’. This association usually occurs on low hills and ridges.
Land systems mapping of the Pilbara region has been undertaken by Van Vreeswyk et al. (2004) and includes consideration of geomorphology, soils, vegetation, land use and resource condition.
Land systems occurring within the North Star project area are shown in Figure 6. The proposed access road lies across seven land systems (Boolgeeda, Boolaloo, Capricorn, Macroy, Platform, River, Rocklea, Talga), whilst the proposed mine site and infrastructure falls within the Capricorn and Boolgeeda land systems. Descriptions of each land system category are provided in Appendix 2.
The Rocklea, Boolgeeda and Macroy land systems are widely represented throughout the Pilbara region. The Capricorn, Talga and River land systems each represent less than 3% area in the Pilbara region. The Boolaloo and Platform land systems each represent less than 1% of area in the Pilbara region. Very small areas of each of these land systems will be impacted by the proposed North Star access road.
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The River land system is characterised by active flood plains and major rivers supporting grassy woodlands, tussock grasslands and soft spinifex grasslands. The proposed access road crosses short sections of these active floodplains.
The River land system is likely to be dependent on surface water and is potentially impacted by the proposed access road. This land system is represented in two small sections of the access road, approximately 2 km in total. It is characterised by active flood plains and major rivers supporting grassy eucalypt woodlands, tussock grasslands and soft spinifex grasslands (Van Vreeswyk et al. 2004).
A detailed assessment of the vegetation of the North Star study area was completed in 2011 by ecologia Environment (2012) and 33 vegetation units were described and mapped. Four of these units occurred in rivers, gorges, creeks and floodplains. These are:
• FpAtCo – Ficus platypoda open woodland over Acacia tumida and Gossypium robinsonii sparse tall shrubland, over Cymbopogon obtectus and Eriachne mucronata sparse tussock grassland,
• ChAbTp – Corymbia hamersleyana open low woodland, over Acacia bivenosa mid shrubland, over Triodia pungens open hummock grassland,
• EvCc (mapped as Cc)– ± Eucalyptus victrix ± Eucalyptus camaldulensis open mid woodland, over Cenchrus ciliaris tussock grassland, and
• PfTp –Pluchea ferdinandi‐muelleri open low shrubland over Triodia pungens sparse hummock grassland.
A further five vegetation units were recorded in drainage lines or shrubby drainage lines: These are
• GwTe – Grevillea wickhamii sparse mid shrubland, over Triodia epactia or Triodia schinzii open hummock
• GwTp - Grevillea wickhamii sparse tall shrubland, over Triodia pungens open hummock grassland
• Ap - . Acacia pyrifolia, Gossypium robinsonii and Tephrosia rosea mid shrubland,
• ApTp - Acacia pyrifolia, Acacia acradenia and Tephrosia rosea mid shrubland, over Triodia pungens open hummock grassland, and
• At - Acacia tumida, Grevillea wickhamii and Indigofera monophylla shrubland.
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4.5 Ecology
A preliminary assessment was made of ecological factors such as significant flora species and vegetation communities that may be dependent on surface water and potentially impacted by changes in surface water flows as a result of the proposed North Star mine and access road. Details of the methodology applied to identify these factors are provided in Appendix 3.
Threatened Communities
There are no Threatened Ecological Communities listed as Matters of National Environmental Significance under the Environmental Protection and Biodiversity Conservation Act 1999 located within the region affected by the North Star project. There are no known occurrences of Threatened Ecological Communities (TECs) or Priority Ecology Communities (PECs) within 30 km of the proposed North Star project.
Surface Flow Dependent Ecosystems
Mulga Sheet-flow vegetation communities have not been mapped as occurring within the North Star project area (ecologia Environment 2012, Beard 1975, Department of Agriculture Western Australia 2005). Information from land system and pre-European vegetation datasets indicate that the surface flow dependent ecosystems present in the North Star project area are likely to be the Eucalyptus camaldulensis riparian woodlands along major drainage lines. ecologia Environment (2012) have described nine vegetation units that occur within rivers, gorges, creeks, floodplains and drainage lines (See section 4.4). Of these, two are most likely to be dependent on surface water flows for at least some of the year and represent riparian vegetation (Figure 7). These are:
• FpAtCo – Ficus open woodland
• EvCc (mapped as Cc) – Eucalyptus open woodland
FpAtCo is restricted to small patches where water cascades over escarpments from areas higher in the landscape and is considered significant (ecologia Environment 2012). This vegetation unit occurs in areas with relatively high levels of moisture and shelter and provides conditions to support habitat specific fauna and flora which may be locally restricted including conservation significant fauna species, such as the Pilbara Olive Python and the Northern Quoll.
EvCc is found on major drainage lines that receive surface water run-off from upstream catchments. This vegetation type was assessed as being in very poor condition by ecologia Environment (2012) as a result of the prevalence of the introduced species Cenchrus ciliaris (buffel grass) in drainage lines that have been grazed by cattle.
The other seven vegetation units described by ecologia Environment (2012) whilst occurring within minor drainage lines are not likely to be dependent on surface water flows as they are likely to be
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SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT ephemeral and only experience flows during periods of intense rainfall and would quickly dry out and remain dry for most of the year.
Threatened and Priority Flora
According to available databases, there are no Threatened Flora records within 30 km of the proposed North Star Mine (DEC 2012a). Ten Priority Flora species have been recorded in this 30 km radius (DEC 2012b) and description records are provided in Table A3.1. ecologia Environment (2012) identified a total of eight Priority Flora species within the North Star survey area. These are:
• Abutilon pritzelianum (P1) • Heliotropium muticum (P1) • Pityrodia sp. Marble Bar (P1) • Euphorbia clementii (P2) • Acacia glaucocaesia (P3) • Gymnanthera cunninghamii (P3) • Goodenia nuda (P4) • Ptilotus mollis (P4)
Of these, Gymnanthera cunninghamii and Goodenia nuda are discussed below:
• Gymnanthera cunninghamii was observed by ecologia Environment (2012) to have high habitat specificity to vegetation unit GwTp, which occurs in sandy drainage channels. These sandy drainage channels are likely to experience flows during high intensity rainfall events, but would quickly dry out and are likely to be dry for most of the year. • Goodenia nuda also showed some habitat specificity for vegetation unit GwTp and ImTp, which correspond to drainage channels and floodplains.
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5. PREDICTED HYDROLOGICAL CHANGE DUE TO NORTHSTAR
MINE SITE
The major impact on flows by the mine is caused by the tailings storage facility, which covers an area of approximately 1500 ha that drains towards the Turner River. The TSF embankment completely cuts-off flow from its catchment to the downstream waterway. However, flow recovers with distance downstream, as additional flow enters from downstream catchments. Figure 8 shows the proportion of natural flows in different reaches of the downstream waterway. It can be seen that the flow proportion recovers to approximately 80% of the natural flow within a distance of approximately ten kilometres from the TSF embankment wall.
The mine pit will also have an impact on flows. However, since the pit lies almost along the catchment divide and is relatively long and narrow the impact on flows will be relatively minor i.e. flows will recover to greater than 80% of the natural flow a short distance downstream of the pit. The stockpile and waste dump will have an impact on the rate of infiltration and the volumes of runoff (which will decrease), but will not materially change the catchment boundaries, therefore impacts on flow will be minor. Drainage associated with the earthworks pads and other infrastructure will only have a minor impact on local flows.
Further, details of surface water impacts are provided in Table 8.
REGIONAL POOLS
A number of regional pools have been identified as part of the Vegetation and Flora Assessment for the North Star project (ecologia Environment (2012)). The mine is not expected to have a significant impact on the pools. Details are provided in Table 9. Note that the majority of the catchment area for the Site 12 Pool lies to the north, away from the waste rock stockpile.
ACCESS ROAD
The access road crosses a number of minor streams which take the form of defined, incised channels. The largest of these drainage channels are likely to support EvCc vegetation. Dense vegetation can be observed along the banks of these channels. Typical terrain is shown in Photos No’s 1-3. The access road is designed for a 1 in 5 year rainfall event with flows up to this event pasing through culverts and bridges. Larger events will spill over the road. Impacts on flow behaviour immedately upstream and downstream of creek crossings will be minor and localised.
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Table 8: Potential Impacts on Surface Flows Catchment Contained Infrastructure Flow related processes Potential Impacts on Flow Mitigation Measures needed (without any mitigation measures) - Stockpile - stockpile may change rate of - minor decrease in runoff - sediment control for disturbed M1 runoff due to increased - water quality of surface runoff areas with exposed soil infiltration may change. - changes in runoff water quality from disturbed areas with exposed soil surfaces.
- Open pit - rainfall on the open pit will be - reduction in catchment runoff - diversion bund/drain to the M2 captured and deducted from from rainfall on open pit. east of the Open Pit to prevent the outflow from this catchment - detention effect of drainage surface water ingress into the (surface water in the pit to be crossings may attenuate the pit. used for processing). peak discharge rate. - drainage crossings for the - with diversion drains runoff - increased runoff from haul/access roads. from east of the pit will cleared/compacted areas. - sediment control for disturbed discharge into the pit - water quality of surface runoff areas with exposed soil. - Increased runoff coefficient may change. from cleared/compacted areas - there is no diversion of runoff (haul roads etc.) due to changes to/from adjacent catchment. in infiltration properties. - changes in runoff water quality
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Catchment Contained Infrastructure Flow related processes Potential Impacts on Flow Mitigation Measures needed (without any mitigation measures) from disturbed areas with exposed soil surfaces. - Stockpile - stockpile may change rate of - minor decrease in runoff - sediment control for disturbed M3 runoff due to increased - water quality of surface runoff areas with exposed soil infiltration may change. - changes in runoff water quality from disturbed areas with exposed soil surfaces.
- Processing plant - increased runoff coefficient - ponding upstream of roads - provide appropriate culverts M4 from cleared/compacted areas and other obstructions. and diversion structures. (processing plant and other - increased runoff from - sediment control for disturbed infrastructure) due to changes cleared/compacted areas. areas with exposed soil in infiltration properties. - water quality of surface runoff surfaces. - changes in runoff water quality may change. from disturbed areas with exposed soil surfaces. - minor roads and sundry - minor flow obstructions and - minor changes to flow rates. - provide appropriate culverts M5 infrastructure local changes to infiltration - water quality of surface runoff and diversion structures. rates may change. - sediment control for disturbed - changes in runoff water quality areas with exposed soil from disturbed areas with surfaces.
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Catchment Contained Infrastructure Flow related processes Potential Impacts on Flow Mitigation Measures needed (without any mitigation measures) exposed soil surfaces.
- minor roads and sundry - minor flow obstructions and - minor changes to flow rates. - provide appropriate culverts M6 infrastructure local changes to infiltration - water quality of surface runoff and diversion structures. rates may change. - sediment control for disturbed - changes in runoff water quality areas with exposed soil from disturbed areas with surfaces. exposed soil surfaces.
- Admin area - increased runoff coefficient - increased runoff from - diversion drains around the M7 from cleared/compacted areas cleared/compacted areas. northern edge of the Stockpile. due to changes in infiltration - water quality of surface runoff - sediment control for disturbed properties. may change. areas with exposed soil - changes in runoff water quality - there is no diversion of runoff surfaces. from disturbed areas with to/from adjacent catchment. exposed soil surfaces. - Waste rock dump - the waste rock dump may - minor decrease in runoff - sediment control for disturbed M8 change the rate of runoff due to - water quality of surface runoff areas with exposed soil increased infiltration may change. - changes in runoff water quality from disturbed areas with exposed soil surfaces.
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Catchment Contained Infrastructure Flow related processes Potential Impacts on Flow Mitigation Measures needed (without any mitigation measures)
TSF - Tailings Storage Facility - TSF covers the site - No runoff from the site - Not applicable
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Table 9: Potential Impacts on Regional Pools Water Pools Easting Northing Major River Potential Impacts on Water Pools Catchments Fig Pool 711673 7650631 Turner River No Project Infrastructure upstream of water pool. No potential impacts expected. Cow Spring 711108 7648592 Turner River No potential impacts expected. Gorge & 713227 7644656 Turner River Located upstream of project area. Rock Pool No potential Impacts expected. Central 704366 7646358 Turner River Located downstream of the project Creek Pool area. Since these infrastructure areas constitute only a small portion of the catchment draining into the water pool, the impact on the water pool is expected to be minor. Northern 712735 7658183 Strelley River No project infrastructure upstream gorge 1 of water pool. No potential impacts expected. Northern 713545 7658568 Strelley River No project infrastructure upstream Gorge 2 of water pool. No potential impacts expected. Echo Pool 714504 7655427 Strelley River No potential impacts expected. Site 12 Pool 716248 7649263 Strelley River Part of the waste dump at the top edge of the catchment may affect the runoff characteristics (volume and quality). Since this area constitutes a small portion of the catchment area draining into the water pool, the impact on the water pool is expected to be minor. Camp Pool 712628 7655633 Strelley River No potential impacts expected. Dirty Water 718242 7655603 Strelley River No project Infrastructure upstream Pool of water pool. No potential impacts expected.
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Photo No 1: Typical terrain for stream crossing access road
Photo No 2: Typical terrain for stream crossing access road
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Photo No 3: Typical terrain for stream crossing access road
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6. REFERENCES:
Beard, J.S. (1975) Vegetation Survey of Western Australia. 1:100,000 Vegetation Series Map Sheet 5 – Pilbara.
Department of Agriculture Western Australia (2005) Pre-European Vegetation – Western Australia. GIS Dataset.
Department of Agriculture Western Australia (2009) Rangeland Land System Mapping for Western Australia. GIS Dataset.
Department of Environment and Conservation (2012a) Threatened (Declared Rare) Database Search.
Department of Environment and Conservation (2012b) WA Herbarium Database Search.
Department of Environment and Conservation (2012c) Threatened Ecological Communities Database Search. ecologia Environment (2012) F Star Vegetation and Flora Assessment. Unpublished report to Fortescue Metals Group Ltd, March 2012 for the North Star Project.
Flavell D. (2005) Design Flood Estimation, Pilbara Iron Ore and Infrastructure Project, for Fortescue Metals Group.
Van Vreeswyk A.M.E., A.L. Payne, K.A. Leighton and P. Hennig (2004) An inventory and condition survey of the Pilbara region, Western Australia. Technical Bulletin No. 92. Department of Agriculture, Western Australia, South Perth.
Water & Rivers Commission (WRC 2000), Surface Hydrology of the Pilbara Region, Report No SWH 32.
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FIGURES
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Figure 1
Page 30 301012-01539 Rev 0 : June 2012 600000 650000 700000 750000 800000
D
E
G
R E Y RIV ER 7750000 7750000 004036
Strelley T
S
358mm/yr E
W
R
E
V I
R 004008 Y L E EL Carlindie TR
S 315mm/yr S
004038 H A
004016 Wallareenya W
Indee 349mm/yr R
I V
328mm/yr E
004059 R
Mallina T 7700000 U 7700000 327mm/yr R Y N E U R L E R
I R V E T I S V A R E K E E R R E E R IV C R E Y L LE I L M E R X 709228 T I 710001 S S Kangan Homestead Upper North Pole 004106 Marble Bar 709010 361mm/yr Pincunah 7650000 7650000 North Star Mine Area
004015 Hillside
7600000 335mm/yr 7600000
004043 Redmont 312mm/yr
LEGEND 7550000 7550000 h Daily rainfall gauging stations X Streamflow gauging stations Railways Major rivers Roads North Star Magnetite Project Proposed Infrastructure Strelley River Turner River
600000 650000 700000 750000 800000
LOCATION PLAN Figure 1. Regional locality North Star Mine
05 10 20 30 40 50 DATE : 03 Aug 2012 SCALE : 1:800,000 at A3 Copyright © Datum : GDA94 CUSTOMER : FMG AUTHOR : M.Rouse WorleyParsons Services Pty Ltd Map Grid of Australia Kilometres ABN 61 001 279 812 Zone 50 MAP : 201012_00350_019.mxd REV : A ProducedBy: M.Rouse - Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_019.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 2
Page 31 301012-01539 Rev 0 : June 2012 710000 715000 7655000 7655000
Tailings Facility
Tailings Pipelines
Water Supply Pipelines North Star Mine Pit
Explosives Store
Waste Dump Chemical Store 7650000 7650000
Stockpile
Accommodation Camp
Substation
Go Line Area Access Road Process Plant Admin and Workshop Transmission Line 7645000 7645000
INFORMATION ONLY NOT TO BE USED FOR CONSTRUCTION
710000 715000
LOCATION PLAN
BROOME Figure 2. North Star mine layout
KARRATHA PORT HEDLAND
0250 500 1,000 1,500 2,000 DATE : 30 Aug 2012 SCALE : 1:40,000 @ A3 CUSTOMER : FMG AUTHOR : M.Rouse Copyright © Datum : GDA94 Metres WorleyParsons Services Pty Ltd Map Grid of Australia CARNARVON MAP : 201012_00350_020.mxd ABN 61 001 279 812 Zone 50
REV : A - By:Produced M.Rouse Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_020.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 3
Page 32 301012-01539 Rev 0 : June 2012 710000 715000 720000 Northern gorge 2 O! Northern gorge 1 Clean Water Pool O! O!
Camp Pool Dirty Water Pool O! Echo pool O! O! 7655000 7655000
TSF
Fig Pool O! 7650000 7650000
Site 12 Pool M1 O!
M7 Cow spring O! M2 M3
M8
M4
M6 M5 O! Legend !O Pools Mine site catchments Waste Dump Stockpile
7645000 Gorge & Rockpool 7645000 O! North Star Mine Pit Tailings Facility Access Road Accommodation Camp Admin, Workshop and SubStation Canning Basin Pipeline Chemical Store Explosives Store Go Line Area Power Infrastructure
INFORMATION ONLY Process Plant NOT TO BE USED Tailings Pipeline FOR CONSTRUCTION
710000 715000 720000
LOCATION PLAN
BROOME Figure 3. Mine site catchments KARRATHA PORT HEDLAND 0250 500 1,000 1,500 2,000 DATE : 30 Aug 2012 SCALE : 1:50,000 @ A3 Metres CUSTOMER : FMG AUTHOR : M.Rouse Copyright © Datum : GDA94 CARNARVON WorleyParsons Services Pty Ltd Map Grid of Australia MAP : 201012_00350_021.mxd ABN 61 001 279 812 Zone 50
REV : A - By:Produced M.Rouse Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_021.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 4
Page 33 301012-01539 Rev 0 : June 2012 690000 700000 710000 720000
ENLARGEMENT 7660000 7660000
00.5 1 2 3 4
Kilometres 7650000 7650000
INFORMATION ONLY NOT TO BE USED FOR CONSTRUCTION
690000 700000 710000 720000 LEGEND LOCATION PLAN Mine access road catchments North Star Mine Pit Explosives Store Figure 4. Project area and BROOME 100 year flood extent Tailings Facility Go Line Area mine access road Railways Access Road Power Infrastructure KARRATHA PORT HEDLAND Rivers Accommodation Camp Process Plant 00.5 1 2 3 4 5 Waste Dump Admin, Workshop and SubStation Rail Siding DATE : 30 Aug 2012 SCALE : 1:100,000 @ A3 CARNARVON CUSTOMER : AUTHOR : Copyright © Kilometres Stockpile Canning Basin Pipeline Stockyard FMG M.Rouse WorleyParsons Services Pty Ltd Datum : GDA94 Map Grid of Australia MAP : 201012_00350_022.mxd ABN 61 001 279 812 Chemical Store Tailings Pipeline Zone 50 REV :
A - By:Produced M.Rouse Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_022.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 5
Page 34 301012-01539 Rev 0 : June 2012 680000 690000 700000 710000 720000
Nicotiana umbratica P: 3
Euphorbia clementii Heliotropium muticum P: 2 P: 1
Pityrodia sp. Marble Bar (G. Woodman & D. Coultas GWDC Opp 4) Euphorbia clementii P: 1 P: 2 *#
Euphorbia clementii 7659979 P: 2 7659979 *#
Pityrodia sp. Marble Bar (G. Woodman & D. Coultas GWDC Opp 4) P: 1
Gymnanthera cunninghamii Gymnanthera cunninghamii P: 3 P: 3 *# 7649979 7649979
Phyllanthus hebecarpus P: 3 7639979 7639979
PreEuropean Vegetation Acacia levata Acacia leeuweniana P: 3 P: 1 Acacia pyrifolia shrubs / Triodia lanigera open hummock grassland *# Acacia levata Acacia levata Grevillea pyramidalis, Hakea lorea, Senna sp. and Grevillea wickhamii shrubs P: 3 P: 3 Triodia pungens and T. wiseana open hummock grassland Eucalyptus leucophloia open woodland Triodia wiseana and T. pungens hummock grassland
INFORMATION ONLY Eucalyptus camaldulensis and Melaleuca leucadendron woodland / Acacia sp. aff. coriacea, NOT TO BE USED FOR CONSTRUCTION Crotalaria cunninghamii, Gossypium robinsonii, Hibiscus panduriformis, Gossypium australe shrubls
680000 690000 Nicotiana700000 umbratica 710000 720000 P: 3 LEGEND LOCATION PLAN Herbarium PTF* Existing Roads Admin, Workshop and SubStation Priority Priority Railways Canning Basin Pipeline BROOME Chemical Store 1 *# 1 Drainage Figure 5. Pre-European Vegetation Explosives Store KARRATHA 2 *# 2 Waste Dump PORT HEDLAND Go Line Area 3 *# 3 Stockpile Power Infrastructure 00.5 1 2 3 4 5 4 North Star Mine Pit Process Plant DATE : 06 Sep 2012 SCALE : 1:150,000 Tailings Facility Rail Siding CARNARVON CUSTOMER : FMG AUTHOR : M.Rouse Kilometers Copyright © Datum : GDA94 Stockyard WorleyParsons Services Pty Ltd Map Grid of Australia Access Road MAP : 201012_00350_023.mxd Tailings Pipeline ABN 61 001 279 812 Zone 50 *Priority and Threatened Flora Accommodation Camp REV :
A - By:Produced M.Rouse Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_023.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 6
Page 35 301012-01539 Rev 0 : June 2012 670000 680000 690000 700000 710000 720000 7660000 7660000 7650000 7650000 7640000 7640000 Land Systems Impacted by Mine Boolgeeda - Stony lower slopes and plains below hill systems supporting hard and soft spinifex grasslands and mulga shrublands Boolaloo - Granite hills, domes and tor fields and restricted sandy plains Capricorn - Hills and ridges of sandstone and dolomite Macroy - Stony plains and occasional tor fields based on granite Platform - Dissected slopes and raised plains River - Active flood plains and major rivers INFORMATION ONLY Rocklea - Basalt hills, plateaux, lower slopes and minor stony plains NOT TO BE USED Talga - Hills and ridges of greenstone and chert and stony plains FOR CONSTRUCTION
670000 680000 690000 700000 710000 720000
LEGEND LOCATION PLAN Waste Dump Access Road Go Line Area BROOME Stockpile Accommodation Camp Power Infrastructure Figure 6. Land systems KARRATHA North Star Mine Pit Admin, Workshop and SubStation Process Plant PORT HEDLAND
00.5 1 2 3 4 5 Tailings Facility Canning Basin Pipeline Rail Siding Roads Chemical Store Stockyard DATE : 06 Sep 2012 SCALE : 1:150,000 CUSTOMER : FMG AUTHOR : Kilometres Railways Explosives Store Tailings Pipeline CARNARVON M.Rouse Copyright © Datum : GDA94 MAP : 201012_00350_024.mxd WorleyParsons Services Pty Ltd Map Grid of Australia Rivers ABN 61 001 279 812 Zone 50 REV :
A - By:Produced M.Rouse Geomatics W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_024.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 7
Page 36 301012-01539 Rev 0 : June 2012 670000 680000 690000 700000 710000 720000
GREAT NORTHERN HWY
KANGAN RD YANDEYARRA RD 7660000 7660000
0125 250 500 750 1,000 0125 250 500 750 1,000
Metres Metres 7650000 7650000
PORT HEDLAND WITTENOOM RD 7640000 7640000
0125 250 500 750 1,000 INFORMATION ONLY 0125 250 500 750 1,000 NOT TO BE USED Metres FOR CONSTRUCTION Metres
670000 680000 690000 700000 710000 720000 LEGEND LOCATION PLAN Ficus - Open Woodland (FpAtCo) Highways Figure 7. Vegetation Mapping (FMG) Eucalyptus - Open Woodland (CC) Roads associated with riparian vegetation PRIORITY FLORA Railways 01 2 4 6 8 10 ") Goodenia nuda Drainage DATE : 06 Sep 2012 SCALE : 1:150,000 !( Gymnanthera cunninghamii Kilometres CUSTOMER : FMG AUTHOR : M ROUSE Copyright © Datum : GDA94 ") Pityrodia sp. Marble Bar MAP : WorleyParsons Services Pty Ltd Map Grid of Australia 201012_00350_017.mxd ABN 61 001 279 812 Zone 50 REV :
A ROUSE By:Produced GeomaticsM - W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_017.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
Figure 8
Page 36 301012-01539 Rev 0 : June 2012 690000 700000 710000 720000 7660000 7660000
Turner Catchment
Strelley Catchment 7650000 7650000
Pincunah Catchment
Upper North Pole/ Shaw River Catchment
INFORMATION ONLY NOT TO BE USED FOR CONSTRUCTION
690000 700000 710000 720000 LEGEND LOCATION PLAN Figure 8. Tailings storage facility % of natural flow remaining Catchments Accommodation Camp Power Infrastructure BROOME Natural Flow (0 - 20%) Waste Dump Admin, Workshop and SubStation Process Plant flow impacts KARRATHA Natural Flow (20 - 40%) Stockpile Canning Basin Pipeline Rail Siding PORT HEDLAND Natural Flow (40 - 60%) North Star Mine Pit Chemical Store Stockyard 00.5 1 2 3 4 5 DATE : SCALE : Natural Flow (60 - 80%) Tailings Facility Explosives Store Tailings Pipeline 30 Aug 2012 1:100,000 CARNARVON CUSTOMER : AUTHOR : Natural Flow (80 - 100%) Access Road Go Line Area Rivers FMG M.Webb Copyright © Kilometres Datum : GDA94 WorleyParsons Services Pty Ltd Map Grid of Australia MAP : 201012_00350_025.mxd ABN 61 001 279 812 Zone 50 REV :
A - GeomaticsBy:Produced M.Webb W.A. Location: I:\Projects\201012-00350- FMG NorthStar Rail\10.0 Engineering\10.05 Geomatics\03Project\Workspace\_SKT\201012_00350_025.mxd
SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
APPENDIX 1: VEGETATION ASSOCIATIONS
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Table A1.1: Vegetation Associations mapped within the North Star exploration area (Department of Agriculture 2005) Vegetation Original Association Original Environmental NVIS Level 6 (SUB_ASSOCIATION) Association Description Mapping Code Description
Hummock grasslands, low Eucalyptus leucophloia open woodland Triodia wiseana and T. 82.1 tree steppe; snappy gum e16Lr t3Hi GEORGE RANGES pungens hummock grassland over Triodia wiseana
Hummock grasslands, ABYDOS PLAIN - Lower 93.3 shrub steppe; kanji over soft a2Sr t1Hi Triodia pungens and T. wiseana open hummock grassland slopes on summits spinifex
Hummock grasslands, ABYDOS PLAIN - Grevillea pyramidalis, Hakea lorea, Senna sp. and Grevillea 93.4 shrub steppe; kanji over soft a2Sr t1Hi CHICHESTER - Oakover wickhamii shrubs spinifex Valley
Eucalyptus camaldulensis and Melaleuca leucadendron Medium woodland; river woodland / Acacia sp. aff. coriacea, Crotalaria cunninghamii, 619.1 gum (Eucalyptus e18Mi ABYDOS PLAIN Gossypium robinsonii, Hibiscus panduriformis, Gossypium camaldulensis) australe shrubls
Hummock grasslands, Acacia pyrifolia shrubs / Triodia lanigera open hummock ABYDOS PLAIN - Mt. 626.1 shrub-steppe; kanji over soft a2Sb t16Hi grassland Tinstone footslopes spinifex & Triodia brizoides
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APPENDIX 2: LAND SYSTEMS WITHIN THE NORTH STAR PROJECT AREA
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Table A2.1: Land Systems within the North Star Project Area
Land Type Land Description Area of land system System represented in the Pilbara region
1. Hills and Ranges Boolaloo Granite hills, domes and tor 1,502 km2, 0.8% with spinifex fields and restricted sandy grasslands plains
Capricorn Hills and ridges of sandstone 5,296 km2, 2.9% and dolomite
Rocklea Basalt hills, plateaux, lower 22,993 km2, 12.7% slopes and minor stony plains
Talga Hills and ridges of greenstone 2,124km2, 1.2% and chert and stony plains
5. Dissected plains Platform Dissected slopes and raised 1,570 km2, 0.9% with spinifex plains grasslands
8. Stony plains with Boolgeeda Stony lower slopes and plains 7,748 km2, 4.3% spinifex grasslands below hill systems supporting hard and soft spinifex grasslands and mulga shrublands
Macroy Stony plains and occasional 13,095km2, 7.2% tor fields based on granite
17. River plains with River Active flood plains and major 4,088 km2, 2.3% grassy woodlands and rivers shrublands and tussock grasslands
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APPENDIX 3: IDENTIFICATION OF ENVIRONMENTAL FACTORS
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Environmentally sensitive areas (ESAs)
A preliminary assessment was made of environmentally sensitive areas (ESAs) that may be dependent on surface water and potentially impacted by the proposed North Star mine or access road. Environmentally sensitive areas (ESAs) are protected under the Environmental Protection (Clearing of Native Vegetation) Regulations 2004. ESAs are selected for their environmental values at state or national levels. They include:
• Declared World Heritage property sites (Environmental Protection and Biodiversity Conservation Act 1999);
• Areas registered on the Register of the National Estate (Australian Heritage Commission Act 1975);
• Defined wetlands and riparian vegetation within 50 m;
• Areas covered by Threatened Ecological Communities (TECs);
• Areas of vegetation within 50 m of Threatened Flora; and
• Bush Forever sites.
Database Searches
Database searches were centered on the proposed North Star mine at the coordinate; zone 50K 699480mE, 7650849mN, using a 30 km search radius.
The Department of Sustainability, Environment, Water, Population and Communities Protected Matters Search Tool provides guidance on matters of national environmental significance or matters protected by the Environmental Protection and Biodiversity Conservation Act 1999, specifically:
• World Heritage properties
• National Heritage places
• Nationally Important Wetlands
• Wetlands of International Significance
• Threatened Ecological Communities
• Threatened Flora species
The Department of Environment and Conservation’s (DEC) database of Threatened Ecological Communities (TECs) and Priority Ecological Communities (PECs) is used to identify communities
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SURFACE WATER STUDIES NORTH STAR MAGNETITE PROJECT
under threat. The DEC’s Threatened Flora database and the Western Australian Herbarium Specimen database are used to identify known and predicted locations of Threatened (T) and Priority (P) flora.
The DEC’s interactive on-line map of Environmentally Sensitive Areas (ESAs) is used to identify areas of native vegetation that are protected under the Environmental Protection (Clearing of Native Vegetation) Regulations 2004.
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WORLEYPARSONS FORMAL REPORT TEMPLATE NORTH STAR MAGNETITE PROJECT
Table A3.1: Department of Conservation and Land Management Threatened and Priority Flora Database search results, requested 8 March 2012.
Cons Species Code Site Vegetation Locality
Ca 120 km S of Port Hedland (27 km N Acacia of Woodstock turnoff, then ca 1 km W of leeuweniana 1 Among granite rocks on granite hill. Spinifex ground cover. Great Northern Highway)
On orange-stained granite outcrop. 7 km N of Obstinate Creek (or 29.1 km Acacia Light orangy-brown gravelly sand Associates include Acacia retivenea, A. pyrifolia N of Woodstock turnoff) on New Great leeuweniana 1 (pH 7). and A. acradenia. Northern Highway
Obstinate Creek Repeater Tower, 13.9 Granitic outcrop and boulder field, Open Scrub of Acacia retivenea subsp. km E of Mount Francisco, 25.2 km SW of skeletal gritty red-grey soil over clandestina, A. tumida var. pilbarensis, Terminalia Pincunah Hill, 28.9 km NW of Woodstock Acacia massive granite and boulder strew, canescens and Cajanus sp. over scattered open Homestead, 18.7 km S of Mount leeuweniana 1 high in landscape. Hummock Grass of Triodia pungens. Tinstone
Acacia c. 125 km S of Port Hedland on Great levata 3 Narrow granite creek with tors. Triodia lanigera hummock grassland. Northern Highway
Ca 120 km S of Port Hedland (27 km N Acacia Granitic sand among granite rocks at of Woodstock turnoff, then ca 1 km W of levata 3 base of granite hill. Spinifex ground cover. Great Northern Highway)
ca 13 km W along unnamed track to Telstra Tower junction with Great Acacia With Acacia stellaticeps, A. orthocarpa (weeping Northern Highway, 122.8 km N of Auski levata 3 Granite outcrop. form), Triodia pungens. Roadhouse
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Cons Species Code Site Vegetation Locality
Distal colluvium in outwash fans. Scattered Low Trees of Corymbia hamersleyana Site: MBW09, South side of track, 1.8 Very gently inclined slope, aspect 80 over Scattered Tall Shrubs of Acacia tumida var. km west of Great Northern Highway on degrees. Coarse fragments common pilbarensis over Open Shrubland of Acacia tumida southern access road to Yandeyarra to maximum size of 20 mm. No var. pilbarensis , Grevillea wickhamii & Acacia Community, 7.7 km NNE of Mt Tinstone, Euphorbia bedrock exposed. Red brown sandy ancistrocarpa over Low Shrubland of Acacia 109.1 km W of Marble Bar, Kangan clementii 2 loam, average depth 33.2 cm. tumida var. pilbaren Station, Pilbara IBRA
Goodenia Drainage line. Mining tenemant. Red nuda 4 soil. Cloudbreak FMG Mine, Pilbara
Gymnanther a cunninghami i 3 Brown-red sand. Open Hummock Grassland of Triodia sp. FMG Stage A Rail Corridor
Hummock grassland with emergent shrubs. Along FMG northern access track E of Heliotropium Flat. Red silty sand. Low lying Associated species include Acacia stellaticeps, Great Northern Highway, 70 km S of Port muticum 1 floodplain. Burnt <3 years ago. Corchorus sp., Triodia sp., Eriachne sp. Hedland
Nicotiana Cool shelter with shade under lee of umbratica 3 large rocks. Soil friable. Abydos Station, S of Port Hedland
Nicotiana Triodia grassland with scattered trees and Road to Nullagine, 2-5 km from junction umbratica 3 Granite outcrops. subshrubs. with Great Northern Highway, Pilbara
Phyllanthus Near the Port Hedland to Newman hebecarpus 3 Highway ca 250 km NW of Newman
Pityrodia sp. 1 Midslope of very steep ironstone With Triodia spp. Unallocated Crown Land, ca 7 km S of
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WORLEYPARSONS FORMAL REPORT TEMPLATE NORTH STAR MAGNETITE PROJECT
Cons Species Code Site Vegetation Locality Marble Bar hillslope, base of small cliff, SW Strelley Station southern boundary, ca (G. facing. Skeletal red-brown sandy 12 km E of Wallareenya Station eastern Woodman & loam over massive ironstone. boundary, E of the Strelley River, ca 90 D. Coultas km SSE of Port Hedland GWDC Opp 4)
Pityrodia sp. Marble Bar (G. Tall shrubland of Terminalia canescens and Unallocated Crown Land, ca 5 km S of Woodman & Base of very steep sandstone Acacia tumida var. pilbarensis over hummock Strelley Station southern boundary, ca D. Coultas hillslope, S-facing, within gorge. grassland of Triodia longiceps, with Eriachne 15 km W of Panorama Station western GWDC Opp Skeletal brown sandy loam over mucronata, Sarcostemma viminale subsp. boundary, just E of the Strelley River. Ca 4) 1 massive sandstone. australe. 90 km SSE of Port Hedland
Bedrock and proximal colluvium. Very gently inclined slope, aspect 150 degrees. Coarse fragments Scattered Tall Shrubs of Acacia inaequilatera over common to maximum size of 600 Scattered Shrubs of Acacia inaequilatera & Site: MBW01, 2 km NE of Pilgangoora mm. Very slight bedrock outcrop. Acacia bivenosa over Hummock Grassland of Mining Centre, 6.9 km N of Mt York, 87.5 Tephrosia Red brown loam, average depth 28.4 Triodia spp. over scattered sedges of Bulbostylis km WNW of Marble Bar, Wallareenya bidwillii 3 cm. barbata over Scattered Herbs of Polycarpaea sp. Station, Pilbara IBRA
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