BHP IRON ORE (GOLDSWORTHY) LIMITED
GOLDSWORTHY EXTENSION PROJECT PHASE II CONSULTATIVE ENVIRONMENTAL REVIEW
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622.341(941.3) DAM BHP Iron Ore CopyA 6z2,3c(qn) .- -
CONSULTATIVE ENVIRONMENTAL REVIEW
The Environmental Protection Authority invites people to make submissions on this proposal.
The Consultative Environmental Review (CER) for the proposed Goldsworthy Extension Project Phase II has been prepared in accordance with Western Australian Government procedures. The report will be available for public comment for four weeks from Monday 2 November 1992.
Comments from government agencies and from the public will assist the EPA to prepare an assessment report in which it will make recommendations to Government.
Following receipt of comments from government agencies and the public, the EPA will discuss the ideas raised with the proponent and may ask for further information. The EPA will then prepare its assessment report with recommendations to government, taking into account the issues raised by the public submissions.
Why write a submission? p A submission is a way to provide information, express your opinion and put forward your suggested course of action including any alternative approach. It is useful if you indicate any suggestions you have to improve the proposal. All submissions received will be acknowledged.
Developing a submission
You may agree or disagree with, or comment on, the general issues discussed in the CER or with specific proposals. It helps if you give reasons for your conclusions, supported by relevant data. You may make an important contribution by suggesting ways to make the proposal more environmentally acceptable.
When making comments on specific proposals in the CER:
clearly state your point of view; indicate the source of your information or argument if this is applicable; and 0 suggest recommendations, safeguards or alternatives. Points to keep in mind I By keeping the following points in mind, you will make it easier for your submission to be analysed.
Attempt to list points so that the issues raised are clear. A summary of your submission is helpfiij. Refer each point to the appropriate section, chapter or recommendation in the CER. If you discuss sections of the CER, keep them distinct and separate, so there is no confusion as to which section you are discussing.
Attach any factual information you wish to provide and give details of its source. Make sure that your information is accurate.
Please indicate whether your submission can be quoted, in full or in part, by the EPA in its assessment report.
Remember to include:
your name your address the date of your submission.
The closing date for submissions is:
Monday 30 November 1992.
Submissions should be addressed to:
The Chairman Environmental Protection Authority 8th Floor 'Westralia Square' 38 Mounts Bay Road PERTH WA 6000
Attention: Ms Jane Aberdeen GOLD SWORTHY EXTENSION PROJECT PHASE II CONSULTATIVE ENVIRONMENTAL REVIEW
prepared for BHP Iron Ore (Goldsworthy) Limited by Dames & Moore Pty Ltd
Job No. 06021-053-071 October 1992 EXECUTWE SUMMARY
BHP Iron Ore (Goldsworthy) Limited proposes to develop an open-cut iron ore mine at Yarrie, located approximately 200km east-southeast of Port Hedland, Western Australia. This development is necessary for the continuation of the Goldsworthy iron ore operations, given the near-exhaustion of high grade iron ore reserves at the current mines at Nimingarra and - Sunrise Hill.
The project involves the removal of overburden, open-cut mining of iron ore, primary crushing and loading of the ore into rail cars for transport to Finucane Island. A village is proposed to be built at Yarrie to house the workforce. Mining of the remnant Nimingarra and Sunrise Hill deposits is planned to continue on a periodic basis in order to fulfil some existing sales contracts.
The mining operation at Yarrie is planned to be carried out by a contractor. A construction workforce of about 200 people and an operational workforce of about 100 is anticipated. The contractor workforce will most likely operate on a long-distance commuting basis.
The Yarrie deposit contains a known reserve of approximately 35 million tonnes of ore in two parts: the relatively shallow Y3 area and the deeper Y2 area. Mining of ore in Y3 is scheduled to begin in December 1993, following a development phase of about 6 months' duration. The extraction rate of ore will be about 5 million tonnes per year.
Overburden from Y3 will be placed in a crescent-shaped gully on the southern side of the Yarrie plateau. Mining of Y2 will follow at a later stage. Once the Y3 pit is mined out, overburden from Y2 will be backiilled into the Y3 pit. At the completion of mining, the overburden will be shaped to blend with the existing landform and rehabilitated. The total quantity of overburden to be mined is about 100 million tonnes.
Water supplies for the mining operation and the accommodation village are planned to be supplied from bores drilled into the Yarrie plateau on the periphery of the pit area. Up to 1,000 klJday is expected to be required. This supply will be augmented, if necessary, by bores installed in the nearby Eel Creek aquifer.
The sourcing of water from the plateau is expected to substantially reduce the need for dewatering of the orebody, which would otherwise be required once mining on the lower benches of the Y2 pit reached the local water table level. If dewatering does prove to be necessary, it will be accomplished either by means of strategically-placed bores or by pumping from a sump in the base of the pit. The high-quality water produced from this dewatering will
be used, wherever possible, for mine-related purposes. If any excess water is produced, it will be discharged to a tributary of Eel Creek, via settling ponds if necessary to remove excess suspended sediments.
The crushed ore will be transported from the mine to Finucane Island by private railway. It is planned to extend the existing Goldsworthy rail line, which currently terminates at the Shay Gap crusher, to Yarrie. Culverts will be utilised along the rail route to minimise - interference with the natural surface drainage and consequent impacts on vegetation downslope of the railway line.
The flora and fauna of the project area are typical of the northern Pilbara. A notable feature is the presence of a large number of mounds just east of the mining area, many of them apparently active, belonging to the Pebble-mound Mouse. The area containing the mounds is outside the area to be disturbed by mining and will be specifically protected.
BHP has identified a number of possible impacts of the project on the environment. These are:
changes to landforms due to construction activities, the mine pit and overburden disposal; soil erosion; release of water produced by pit dewatering during the later stages of the project; drawdown of groundwater due to abstraction for water supply; possible seepage of saline water from the mined-out pit in the very long term; interruptions to surface water flows ('shadowing") by the railway line; loss of vegetation and fauna habitat; barrier effects of the railway line on fauna; noise and dust; and potential for release of hazardous materials (fuel and oils, etc.).
BHP has prepared an environmental management programme to avoid or manage these impacts. The overall aim of the environmental management programme will be to minimise impacts through a "minimum clearing" policy, minimum abstraction of groundwater, careful monitoring of impacts and comprehensive rehabilitation. BHP has developed rehabilitation procedures through its experience in the Pilbara region and will apply this experience to rehabilitation at Yarrie. The object of the rehabilitation programme will be to ensure that, at the end of the project, disturbed surfaces (with the exception of the mine pit) are returned to a stable condition with a flora and fauna that resemble the natural condition of the site.
BHP has held discussions with the Aboriginal custodians of the Yarrie area and with the pastoralists on whose leases the project area is located. Agreement has been reached between the company and the other parties on avoiding or mitigating any adverse effects of the proposal on their interests in the area.
The investigations undertaken for this CER have shown that the environmental impacts of the Yarrie project will be fairly minor and easily managed. BHP is committed to managing any impacts that cannot be avoided. (iv)
TABLE OF CONTENTS
Page No.
1.0 INTRODUCTION 1 1.1 THE PROPOSAL 1 1.2 THE PROPONENT 1 1.3 LOCATION AND TENURE 1 1.4 HISTORY OF THE PROPOSAL 2 1.5 EXISTING FACILITIES 3
2.0 PROJECT DESCRIPTION 4 2.1 INTRODUCTION 4 2.2 MINING 4 2.2.1 Construction 4 2.2.2 Mining Method 5 2.2.3 Mining Schedule 6 2.2.4 Pit Dewatering 7 a 2.3 OVERBURDEN MANAGEMENT 8 2.4 ORE PROCESSING 9 2.5 TRANSPORT OF PRODUCT 9 2.6 WATER SUPPLY 11 2.7 WORKFORCE AND ACCOMMODATION 12 2.7.1 Workforce 12 2.7.2 Accommodation 13 2.8 INFRASTRUCTURE AND SERVICES 14 2.9 EXPLORATION POTENTIAL 17
3.0 EXISTING ENVIRONMENT 18 3.1 REGIONAL SETI'ING 18 3.2 GEOLOGY AND GEOMORPHOLOGY 18 3.3 TOPOGRAPHY 18 3.4 SOILS AND ERODIBILITY 19 3.5 HYDROLOGY 19 3.5.1 Regional Hydrology 19 3.5.2 Local Hydrology 20 3.5.3 Water Resources 21 (v)
3.6 CLIMATE 21 3.7 VEGETATION AND FLORA 23 3.8 FAUNA 24 3.8.1 Introduction 24 3.8.2 Habitats 24 3.8.3 Vertebrate Fauna 24 3.8.4 Rare Fauna 25 3.8.5 Feral Fauna 26 3.9 ABORIGINAL HERITAGE 26 3.10 EUROPEAN HERITAGE 27 3.11 EXISTING LAND USE 27 3.11.1 Pastoral Leases 27 3.11.2 Tourism and Sightseeing 27 fl 4.0 ENVIRONMENTAL IMPACT ASSESSMENT 28 4.1 LANDFORMS 28 4.1.1 Construction Earthworks 28 4.1.2 Borrow Pits 28 4.1.3 Erosion 29 4.2 SURFACE HYDROLOGY 29 4.3 HYDROGEOLOGY 30 4.4 FLORA AND FAUNA 31 4.4.1 Impacts on Flora 32 4.4.2 Impacts on Fauna 32 4.4.3 Impact on Wetlands 34 4.5 NOISE AND DUST 34 4.6 HAZARDOUS MATERIALS 35 4.7 WASTE PRODUCTS 35 4.8 FIRE 35
5.0 ENVIRONMENTAL MANAGEMENT AND MONITORING PROGRAMME 36 5.1 LANDFORMS 36 5.1.1 Construction Earthworks 36 5.1.2 Borrow Pits 36 5.1.3 Erosion 36 1 1 (vi)
5.2 SURFACE HYDROLOGY 37 5.2.1 Pit Dewatering 37 5.2.2 Effects of Railway Line 38 5.3 HYDROGEOLOGY 38 5.3.1 Drawdown of Groundwater 38 5.3.2 Salinity Build-up in Y2 Pit 39 5.4 FLORA 39 5.4.1 Railway Line 39 5.4.2 Weeds 40 5.5 FAUNA 40 5.5.1 Railway Line and Road Kills 40 5.5.2 Pebble-mound Mouse 41 5.5.3 Other Fauna Protection Measures 42 5.6 NOISE AND DUST 42 5.6.1 Noise 42 5.6.2 Dust 42 5.7 HAZARDOUS MATERIALS 43 5.8 OILY WASTES 43 5.9 OTHER WASTE PRODUCTS 44 5.10 FIRE 44 5.11 REHABILITATION 45 5.11.1 Aim of Rehabilitation 45 5.11.2 Post-Construction Rehabilitation 45 5.11.3 Rehabilitation of Overburden 45 5.11.4 Decommissioning 46 5.11.5 Monitoring of Rehabilitation 46
6.0 SOCIAL IMPACTS AND MANAGEMENT 47 6.1 INTRODUCTION 47 6.2 VISUAL IMPACTS 48 6.2.1 Visibility 48 6.2.2 Impact on Scenic Values 48 6.3 ABORIGINAL INTERESTS 48 6.4 IMPACTS ON EXISTING LAND USES 49 6.4.1 Pastoral Leases 49
J (viii)
LIST OF TABLES
Table No. Title 3.1 Climatic Averages - Goldsworthy
LIST OF FIGURES
Figure No. Title 1.1 Location Map 1.2 Northern Pilbara Tenements 2.1 Project Area Layout 2.2 Ultimate Pit Design 2.3 Yarrie Pit Cross-section 3.1 Yarrie Geological Setting 3.2 Yarrie Ore Body: Typical Cross-sections 3.3 Eel Creek Aquifer 3.4 Yarrie Ore Body: Hydrogeology
LIST OF PLATES
Plate No. Title 1 Yarrie Mine Site 2 View of Project Area 3 View of Railway Route
LIST OF APPENDICES
Appendix Title A EPA Guidelines for Preparation of the CER B Report of Vegetation Surveys C Report of Fauna Survey D BHP-Newman Guidelines and Objectives for Borrow Pit Development and Rehabilitation
The base map used in Figure 2.1 is Crown Copyright and is reproduced with the permission of the General Manager, Australian Surveying and Land Information Group, Department of Administrative Services, Canberra, ACT. GOLDS WORTHY EXTENSION PROJECT
CONSULTATWE ENVIRONMENTAL REVIEW
1.0 INTRODUCTION
1.1 THE PROPOSAL
BHP Iron Ore (Goldsworthy) Limited (referred to in this document as BHP) proposes to develop an open-cut iron ore mining operation at Yarrie, located approximately 200km east-southeast of Port Hedland, Western Australia. This proposal is subject to the Iron Ore (Goldsworthy-Nimingarra) Agreement Act 1972. The proposal was referred to the Environmental Protection Authority (EPA), which set a formal assessment level of Consuitative Environmental Review (CER) for the project. This CER is submitted for public review and to assist Government to determine the environmental acceptability of the project. The EPA has provided guidelines for the preparation of the CER and these are attached in Appendix A.
1.2 THE PROPONENT
The Goldsworthy operations are owned by the Mount Goldsworthy Mining Associates Joint Venture. The Joint Venture partners are
BHP Australia Coal Limited 30% BHP Iron Pty Limited 55% Mitsui Iron Ore Corporation 7% C I Minerals Australia Pty Limited 8%
The manager of the project is BHP Iron Ore (Goldsworthy) Limited, whose address is 200 St George's Terrace, Perth, Western Australia.
1.3 LOCATION AND TENURE
The Yarrie project is located in the Pilbara region of Western Australia (Figure 1.1). Mining and exploration leases held by the joint venture in the immediate project area (Figure 1.2) are:
Kennedy Gap ML249SA Sect 5 Cattle Gorge ML249SA Sect 6 Yarrie ML263SA Sect 4, 6, 7 and 8 E 45/1072
Pa,c'ool cp_ V.D6 Grey N -RIDLEY ORDAREA PORT HIjDLAND ML2\1<
•Popegarrs 646/ 1076 11 ; N. SHAY GAP
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I Existing railroad BHP fron )r Area A M.L 286 BA Area B M.L 249 BA (21 8ectlona) Proposed railroad BHP IRON ORE Area 0 M.L 251 SAThtL 263 BA (8 3ectIoni (GOLDSWORTHY) LTD. Town NORTHERN PILBARA Exploatlon Ucence areae 1-lomestead TENEMENTS
BHP02 Oct 1992 FIGURE 1.2 -2-
The joint venture holds a Special Lease (No. 3 116/5978) for a rail line connecting Shay Gap and Kennedy Gap, which was the originally proposed railway alignment for Phase II of the Extension Project. The rail extension now proposed for Yarrie is positioned further south than this Special Lease, which therefore will be surrendered in the future.
1.4 HISTORY OF THE PROPOSAL
The iron ore deposits at Mount Goldsworthy were mined out in December 1982 and all mining operations have since been concentrated at Shay Gap and Sunrise Hill. However, the economically mineable high grade ore reserves in these areas were limited and are now close to exhaustion.
Plans to mine at Yarrie were outlined in November 1985 in the "Goldsworthy Extension Project", copies of which were submitted to the State Government of Western Australia through the then Department of Resources Development (now Department of State Development). The project was divided into two distinct phases: Phase I - Mining of Nimingarra, Sunrise Hill and Shay Gap areas; and Phase H- Kennedy Gap and Yarrie. A Notice of Intent for Phase I (GML, 1986) was submitted in December 1986 which indicated that this phase would continue through to the year 1999.
Phase II of the Goldsworthy Extension Project, as briefly outlined in GML (1986), was due to commence in 1999. Since the acquisition by BHP Minerals and its Japanese partners in 1990 of the remaining shareholding in the Goldsworthy mining operations, an intensive drilling program has taken place in 1991192 throughout the Nimingarra/Shay Gap area as well as the Yarrie area. This program has shown that the life expectancy of the remaining ore reserves at NimingarralShay Gap is much shorter than was originally thought.
Conversely, the mineable reserve shown to exist at Yarrie is an increase on original estimates. Although there is a requirement to remove a large volume of overburden, the high grade of the ore, combined with other technical advantages, dictates that the immediate development of Yarrie is necessary for the continued viability of the total Goldsworthy operations. As a result, the proposal to mine at Yarrie has been moved forward, with the aim of commencing full production in 1994.
The project is designed to meet a market demand in a strongly competitive international industry. The ore must be produced at a cost and time that can satisfy the market demand so that existing and potential customers are not forced to seek alternative sources.
N -3-
1.5 EXISTING FACILITIES
A number of small deposits at Nimingarra, Sunrise Hill and Shay Gap have been mined using conventional open cut methods. Mined ore is primary-crushed at Nimingarra and Shay Gap before being transported by rail to the secondary and tertiary crushers, beneficiation plant and ship loading facilities at Finucane Island.
Company towns have been constructed at Finucane Island, Goldsworthy and Shay Gap. The town of Goldsworthy was vacated in July 1992 and removal of all structures and rehabilitation is in progress. The company also maintains a large number of houses in South Hedland. Other infrastructure constructed and maintained by the company includes private roads linking the company's operations to the main road system, and airstrips at Goldsworthy and Shay Gap. -4-
2.0 PROJECT DESCRIPTION
2.1 INTRODUCTION
The project involves the mining, using conventional open-cut methods, of iron ore and overburden, primary crushing and loading of the ore into rail cars for transport to Finucane Island. Ancillary features of the proposal are the village, water supply, power supply and sewage treatment facilities. The layout of the various elements of the project is shown on Figure 2.1. Plate 1 shows a general view taken from the top of the Yarrie plateau looking south-west.
2.2 MINING
2.2.1 Construction
Construction is planned to commence in April 1993, subject to the granting of the necessary approvals. The construction phase will involve the extension of the rail line and power line from Shay Gap to Yarrie and the installation of the crushing plant, stockpiling and trainloading facilities, and the construction of the village, offices and workshops.
The construction phase is expected to last for 9 months. The construction workforce, employed under the AWU Construction Award, will peak at about 200 people approximately 4 months into the construction programme.
The construction workforce will be housed in an on-site demountable camp, as is the standard cost-effective practice in mine construction. This arrangement will be used to minimise the travel time and costs involved in commuting arrangements for a short-term workforce.
Construction Workforce Accommodation Alternatives Consideration has been given to the following alternatives for housing the construction workforce:
accommodation at Shay Gap; accommodation at Newman or Port Hedland; and 0 camp accommodation on site (the chosen alternative).
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DAMES & MOORE FIGURE 2.1
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Mining will continue at Shay Gap until the end of 1993. Shay Gap will be fully occupied until that time, with only limited vacancies occurring. Accommodation for the construction workforce at Shay Gap is therefore unavailable.
Accommodation of a large, short-term workforce at Port Hedland (200km away) or Newman (312km away by air) would incur substantial cost and time penalties due to the distances involved and the lack of sufficient suitable housing at these centres.
The chosen option of on-site camp accommodation was selected because it ensures that the rapid expansion and contraction of the construction workforce can be accommodated. Its proximity to the project will minimise commuting time, enabling the construction to be completed in the most efficient and cost-effective manner.
2.2.2 Mining Method
The mining method proposed for Yarrie is the same as that currently utilised at Nimingarra and Sunrise Hill. This will involve the selective removal of overburden and the opening up of the ore body for conventional open-cut mining. The overburden and ore will be excavated by means of drilling, blasting and loading by a large hydraulic excavator and large front end loaders into off-highway dump trucks for transport to the crusher or overburden site as appropriate. The rate of extraction of high grade ore is planned at about 5 million tonnes per year, depending on sales contracts.
The proposed mining face height is 12 metres, which is the height currently employed at the Nimingarra/Sunrise Hill operation. It is anticipated that blasthole drilling will be undertaken with drills equivalent to a BE 60R, producing 310mm diameter holes. Conventional ANFO or water-resistant gels will be employed as the blasting agent. It is envisaged that an excavator equivalent in size to a Liebherr 994 and front end. loaders equivalent to a Cat 994 will be employed to. load the ore and overburden material. The off-highway dump trucks will be of a size equivalent to a Cat 785 or Cat 789.
The design of the mine pit walls has been carried out by BHP Engineering Pty Limited (1992) using the GALENA software package, as used by the Department of Minerals and Energy. From this preliminary work, the following pit design criteria were established: Final wall bench height 24 m Berm width - north wall 6 m -southwall 8m Clean-up berm width north wall 13.5 m - south wall 16 m Clean-up berm interval 72 m
Final wall bench angle 650 Road width 25 m Road gradient 1:10
Overall slope angle 500
The ultimate pit plan is shown on Figure 2.2 and a pit design cross-section is shown on Figure 2.3.
Mining of the remnant Nimingarra/Sunrise Hill deposit is planned to continue on a periodic basis in order to fulfil some existing sales contracts. This mining will be carried out on a smaller scale than at present.
A contract mining operation is planned for Yarrie. This type of operation is seen as the most appropriate method due to:
the relatively short life of the deposit; uncertainty regarding market acceptance of this 'new" ore; mining flexibility required for: - variations in overburden and ore mining requirements - variations in production levels due to changing market demand; the high initial overburden to ore ratio; the relatively short development time available; elimination of the requirement for up-front capital expenditure such as mobile equipment purchases; and the requirement for periodic mining at Nimingarra/Sunrise Hill.
2.2.3 Mining Schedule
The Yarrie ore body, although one continuous deposit, has a deep section (Y2) at the south-western end and a shallower section (Y3) to the north-east. A development phase of S SURFACE 274 262
250
238
226
214
202 c CLEANUP BERM CLEANUP BERM .190
.178
kp 166
.164
142
HAUL ROAD 130 CLEANUP BERM 118
06 BERM 94
82 HAUL ROAD TO
FACE ANGLE 65° 58
. 45
II I I I I 600 550 500 450 400 350 300 250 200 ISO 100 50
MINING I DATE I 20-10-92 WORK BY S ERVICES BHP IRON ORE (GOLDSWORTHY LTD.) PREPARED D. WILKINSON. BHP REVISED Engineering DRAWN N. TAYLOR. PIT DESIGN SECTION S Mining Services FIGURE 2.3 CENTRE I PERTH - 7..-
approximately 6 months' duration is required to remove around 5 million tonnes of overburden and low-grade ore to uncover the high grade iron ore. This development mining will commence in the Y3 part of the deposit, with mining of high grade ore scheduled to begin in December 1993. The reason for mining Y3 first is that this area has relatively little overburden to be removed, thus enabling mining of the high grade ore to commence in the shortest possible time.
Mining of Y2 will commence in the first year of operations. A large quantity of overburden is first required to be removed from this area to uncover the high grade ore.
The extraction rate of saleable ore is proposed at about 5 million tonnes per year. A total known reserve of approximately 35 million tonnes has been identified with a strip ratio of about 2.8:1 (overburden:ore).
The total area of ground disturbance by all aspects of the project in the first twelve months is estimated to be:
Mine Pit 104 ha Overburden site 112 ha Railway line 50 ha Infrastructure (power lines, roads, etc.) 10 ha Buildings (village, office/workshop, etc.) 34 ha Borrow pits 40 ha Airstrip 4 ha Total 354 ha
In most cases, these areas represent the maximum that will be disturbed during the life of the project.
2.2.4 Pit Dewatering
The majority of the Yarrie deposit is well above the groundwater table. However, the lower parts of the Y2 pit will require dewatering once the base of the pit reaches below the water table level. By that time, substantial dewatering is expected to already have been achieved through the abstraction of water from the plateau for domestic and process water supply. Dewatering will be achieved either with strategically-located bores or by pumping from a sump in the base of the pit. Water produced from dewatering will be used for domestic water supply, dust control and other mine-related purposes. Any excess will be discharged into a tributary of Eel Creek. This is discussed further in Section 4.2.3.
2.3 OVERBURDEN MANAGEMENT
The total quantity of overburden to be removed from the Yarrie deposit is approximately 100 million tonnes. Overburden will be placed in a crescent-shaped gully on the southern side of the Yarrie plateau (Figure 2.1; Plate 1). This location will enable the overburden to blend with the natural topography of the plateau. The overburden will occupy a site approximately 112ha in area and the top of the overburden will be approximately level with the top of the plateau. A portion of the overburden will be used in the later stages of mining to partially backfill the Y3 pit.
The overburden will be deposited in stages so as to achieve an overall slope of 200 on the outer face, which will be shaped to blend with the existing landform. At the completion of mining, the surface of the overburden will be rehabilitated.
Alternative Overburden Management Strategies The alternatives available for overburden management were:
depositing the majority of the material in the location shown on Figure 2.1, with some overburden being backfilled into the Y3 pit (the chosen option); temporary stockpiling of overburden, with all material being backfilled into the Y2 and Y3 pits at the cessation of mining; and depositing the overburden on top of the Yarrie plateau.
The chosen option was selected for the following reasons:
the overburden will blend neatly into the profile of the plateau at that point. The site contains no significant vegetation associations, fauna habitats or drainage lines; placement of overburden can be carried out simultaneously with mining, with no requirement for double-handling of overburden. Once the Y3 pit is mined out, it can be partially backfilled with overburden from the Y2 pit; and 0 the site offers the minimum haulage distance from the pit.
I
The rejected option of temporary stockpiling followed by backfilling would have eliminated the need for permanent overburden storage and would avoid the formation of a standing water body in the mined-out pit. The option had, however, some critical disadvantages:
some 100 million tonnes of overburden would need to be backfilled at great cost, at a time when no further income was being generated. This would make the entire project uneconomic; the site of the temporary stockpile would be severely disturbed and would present a rehabilitation task similar in magnitude to a permanent overburden storage site; the bulk (volume) of the overburden would be considerably increased by excavation and handling. The overburden could not, therefore, all be accommodated in the pit and a mound would be left at the conclusion of backfilling.
The alternative of depositing the overburden on top of the plateau was rejected because:
it would be highly visible; storage at this location would increase the haulage distance for overburden; and it could have adverse environmental impacts, such as disturbance to Pebble-mound Mouse habitat (see Section 6.8.4).
2.4 ORE PROCESSING
The existing Shay Gap primary crusher will be relocated to Yarrie. The crusher will be positioned on the edge of the Yarrie plateau in the general location indicated on Figure 2.2 to take advantage of the height of the plateau to reduce haulage distance.
Ore will be tipped into the crusher direct from haul trucks or loader-fed from adjacent run-of-mine stockpiles. Primary crushing will take place to produce a nominal -150mm size product. The primary-crushed ore will be conveyed to a train loading facility, again relocated from Shay Gap, for loading onto rail cars. Allowance will be made in the design for the future installation of secondary crushing facilities to produce a -100mm size product.
2.5 TRANSPORT OF PRODUCT
The primary crushed ore will be transported by private railway from the mine to the secondary and tertiary crushing and ship loading facilities at Finucane Island. Trains will consist of up to 130 cars, each carrying 75 tonnes of ore. Several trains per day will run in each direction. - 10 -
It is planned to extend the existing Goldsworthy rail line, which currently terminates at the Shay Gap crusher, to Yarrie. The planned extension of approximately 25 kilometres will run in a south-easterly direction through Shay Gap, north of Cundaline Ridge and across Eel Creek to terminate in a loop in Kimberley Gap between the Yarrie and Callawa plateaux. This route is shown on Figure 2.1.
Numerous minor drainage lines will be crossed by the railway line. Most of these carry water from Cundaline Ridge to creeks north of the railway route. Culverts will be utilised along the rail route to minimise interference with the natural surface drainage. West of Eel Creek, the alignment has been kept to the southern side of a large tributary to minimise major waterway crossings. Large culverts will be utilised to cross Eel Creek. Culverts will generally be designed to accommodate a 1-in-5 year flood event, with a maximum of 300mm flow over the rail embankment. At major creek crossings such as at Cooneeina Creek and Eel Creek, sacrificial sections of track will be laid next to the crossing so as to localise any flood dam age which does occur to the line. Some upstream and downstream "training" of drainage channels will be carried out where several channels occur close together in the vicinity of a culvert. The effect of this training will be to redirect drainage channels within a short distance either side of the culvert (typically up to 50m) so that they pass through the culvert, and then to disperse them again on the downstream side. This will reduce the possibility of flood damage to the rail embankment and minimise the effects of the embankment on the overall surface drainage in those areas.
Alternative Rail Alignments Three options were considered for the railway line route:
the chosen route; a route located several kilometres to the north of the chosen route, passing near Cattle Gorge before heading south-east past Lakes Bore to terminate in Kimberley Gap (following, in part, the Kennedy Gap Railway Special Lease No. 3116/5978); and a route to the south of Cundaline Ridge and Mundarinya Ridge which passed close to Yarrie homestead and followed part of Eel Creek north from the De Grey River before terminating in Kimberley Gap. The proposed alignment was chosen for the following reasons:
the length of line required was minimised; the route avoids areas close to the De Grey River that may be susceptible to flooding; the terrain is reasonably level, thereby avoiding major cut-and-fill; and no sensitive areas are crossed or disturbed by the route.
The northern option was rejected because:
it would have impinged on a significant Aboriginal ethnographic site near Lakes Bore; and it was longer than the chosen route, making construction and operation more expensive and creating more ground disturbance.
The southern option was rejected because:
unfavourable grades existed at the Shay Gap end of the route; the route passed close to Yarrie homestead and cattle holding paddocks near Eel Creek; the route could be susceptible to flooding from the De Grey River and the lower reaches of Eel Creek; and the route was considerably longer than the chosen route, resulting in higher construction and operating costs and creating more land disturbance.
2.6 WATER SUPPLY
Water supplies will be obtained preferentially from bores drilled into the Yarrie plateau adjacent to the ore body, augmented if necessary from a borefield in the nearby Eel Creek aquifer. The final choice of source will depend on the results of water quality and yield investigations currently underway.
Up to 1,000kl/day of water is expected to be required for drinking and domestic purposes at the village and mine site, and for dust suppression at the mine. The expected breakdown of water usage is:
Domestic use 200 kllday Mine use/dust suppression 800 kllday Total usage 1,000 kllday. - 12 -
2.7 WORKFORCE AND ACCOMMODATION
2.7.1 Workforce
It is envisaged that the mining contractor will operate his workforce on a periodic work/recreation shift system in accordance with the Australian Workers' Union (AWU) Mining Industry Award 1990. An operational workforce of about 100 people is anticipated for the project, including BHP and contractor personnel. The source and size of the workforce will be at the discretion of the mining contractor.
The contractor will be encouraged to source the operational workforce from the Pilbara, including Karratha and Wickham as well as Port Hedland and Newman. Former BHP Iron Ore employees accepting redundancy from Shay Gap will, if they indicate interest, be made known to the contractor and, if suitable, the contractor will be encouraged to employ them.
An assessment of the availability of appropriately skilled labour in the Pilbara will be obtained from the Karratha and Port Hedland offices of the Commonwealth Employment Service and will be provided to the mining contractor.
Workforce Alternatives The Yarrie project is a small-scale operation, with a short life and high pre-development costs - including pre-stripping and rail construction. It is aimed at meeting a market opportunity in a particularly difficult period for the international iron ore industry. Rapid, low-cost development is therefore critical.
BHP closely examined the relative merits of utilising a contractor-based mining operation at Yarrie versus the option of maintaining a company-based workforce.
A contract mining operation was seen as the most appropriate method of mining the relatively small Yarrie ore body and the remaining ore at Nimingarra. Flexibility of operation is necessary to vary ore and/or overburden movement as appropriate to meet market demand and the variation of the individual orebodies. Without such flexibility, the overall Goldsworthy operations could not compete internationally and would need to be suspended.
up
- 13 -
2.7.2 Accommodation
A village will be constructed to the north-west of the mine site at sufficient distance so as not to be disturbed by the mining activity. The proposed location of the village is shown on Figure 2.1. The village will consist of full accommodation, messing and recreation facilities for the entire operational workforce. The design of the village will be similar to that recently constructed at BHP's Yandi project.
, The project will mainly operate on a long-distance commuting basis, with personnel flying from the Yarrie airstrip to Port Hedland, other Pilbara centres or Perth. A commuting system is seen as the most appropriate method of operation for an anticipated workforce of 100. If a permanent site-located workforce was used, additional services and facilities such as schools, police, medical centre and shopping complex would be required. A workforce of 100 is insufficient to justif' these facilities. /
Alternative Accommodation Arrangements The alternative accommodation arrangements considered were:
construct a village at Yarrie; maintain the existing Shay Gap township and commute to Yarrie; or provide housing in Newman or South Hedland with workers commuting daily to Yarrie.
BHP chose a village at Yarrie for the following reasons:
o The estimated workforce of 100 people at Yarrie is too small to support a town the size 4 of Shay Gap (which currently accommodates a workforce of about 300 and a total population of about 860 people).
Shay Gap was erected as a temporary township in 1972. It is now in need of major and costly refurbishment and is an uneconomic impost on the existing operations. Its retention for a workforce of 100 would not only be impractical but would preclude the social amenities of a normal town.
The environmental impact of establishing a village at Yarrie will be more than compensated for by the complete rehabilitation of the present Shay Gap townsite. After the removal of the village, that site will also be rehabilitated. 14 -
BHP Iron Ore is giving its employees at Shay Gap considerable time to choose their options, i.e.: - a redundancy package, - a transfer to other BHP Iron Ore operations, or - an opportunity to seek employment with the contractor selected for the Yarrie project.
Further discussions are continuing with the Shay Gap employees and, until their preferences are known, it is premature to assume that they would choose to live in designated locations. For example, BHP Iron Ore is conscious of the enormous social problems in South Hedland and, while BHP is assisting with attempts to resolve those problems, it would be reluctant to create further ones. Studies of long-distance commute experiences in the Western Australian mining industry have shown that social problems are minimised when workers can choose their place of residence. Where a contract workforce chooses to work under a long-distance commute award with an open employment origin, there are generally few unfilled vacancies.
Most of the economic disadvantages of housing people in Shay Gap would also be attached to housing in Port Hedland or Newman, with the added costs of commuting and a camp for temporary site accommodation. Mining unions have recently lodged "living away from home allowance" claims for people locally employed from Port Hedland, in the view that all employees should receive the same benefits whether or not they are required to live away from home. This would add to the economic disadvantages of employing Pilbara-based people, when a larger pool of skilled workers is available in Perth.
2.8 INFRASTRUCTURE AND SERVICES
All necessary infrastructure and services will be established at the Yarrie mine site. These facilities will consist of:
village; airstrip; mine offices; 0 workshop; 0 parking areas (mine plant and light vehicles);
- 15 -
fuelling facilities; power supply; telecommunications facilities; water supply facilities; and explosive stores.
An airstrip for light aircraft will be constructed close to the village site. Its location is shown on Figure 2.1. The airstrip will be designed in accordance with the Civil Aviation Authority's 1 Guidelines for Aeroplane Landing Areas No. 92-1(0), for light aircraft equivalent in size to a Cessna Conquest.
The mine facilities, including offices and workshops, will be located either on the plain west of the mine or, if preferred by the mining contractor, on the top of the plateau north of the mine pit. These locations are shown on Figure 2.1. The position on top of the plateau has some advantages in terms of proximity to the mine and removal of the need to drive equipment down from the plateau for servicing. Both sites are far enough from the pit to avoid blast damage.
Fuel will be stored in above-ground tanks held in impermeable bunded enclosures, in accordance with current Department of Minerals and Energy (DOME) regulations. The explosives storage compound will be located in a remote area away from the mine and other infrastructure.
By arrangement with the manager of Yarrie Station, a fence will be constructed across the gap between Callawa and Mundarinya ridges, to exclude station cattle from the mine area.
Telecommunications will be provided at the mine by extension of the microwave link that currently connects Shay Gap to the Telecom Australia network at Port Hedland.
Power for the village, mine offices, workshop, crushing and train loading facilities will be sourced from the Goldsworthy 66kV line that currently terminates at the Shay Gap township. A 22kV power line will be extended to Yarrie along the approximate alignment shown on Figure 2.1. - 16 -
Power Supply Alternatives Three alternatives for power supply were considered:
a 22kV power line from the Shay Gap townsite on the current alignment (Figure 2.1); a 22kV power line from the Shay Gap crusher on the approximate alignment of the railway route; a 66kV power line from the Shay Gap substation; and on-site generation at Yarrie.
The current power line alignment was chosen because:
the length of line required is similar to or less than that of the alternatives; and the capacity of the existing 22kV line from the Shay Gap substation to the Shay Gap townsite (10 megawatts) is adequate for the expected demand at Yarrie.
The option of a 22kV line from the Shay Gap crusher was rejected because the capacity of the existing line from the Shay Gap substation to the crusher (3 megawatts) was insufficient to meet expected Yarrie demand.
The option of a 66kV line from the Shay Gap substation was rejected because:
the length of line required was 7km more than for the chosen option; the 66kV line itself was more expensive than 22kV line; and a new substation would be required at Yarrie to step the power down from 66kV to 22kV before distribution.
The option of on-site generation at Yarrie was rejected primarily on the grounds of cost. With the existence of SEC WA supplies at Shay Gap, establishment of a generating capacity at Yarrie would be expensive due to the costs of installing, running and maintaining the plant. In addition, the use of SEC WA supplies will help to minimise the emission of greenhouse gases. - 17 -
2.9 EXPLORATION POTENTIAL
Several other deposits of iron ore have been identified in the vicinity of Yarrie. These are:
low-grade crustal deposits scattered to the north of Yarrie; a high-phosphorus deposit in Kennedy Gap; and a low-grade deposit in Cattle Gorge.
Under the present world iron ore market conditions, it is unlikely that these deposits will be mined in the immediate future. If mining at some stage is proposed, it will be the subject of a separate proposal.
FA
- 18 -
3.0 EXISTING ENVIRONMENT
3.1 REGIONAL SETFING
The Yarrie Project is located in the northern Pilbara region of Western Australia, approximately 30km south-east of Shay Gap. The closest major population centre is Port Hedland, the major service centre for BHP's iron ore processing and shipping operations.
3.2 GEOLOGY AND GEOMORPHOLOGY
The Yarrie iron ore deposit is located adjacent to the southern escarpment of a prominent east-west trending range that rises about 120 metres above the level of the surrounding plain. It occurs within a thick sequence of Archaean-age banded iron formation (BIF) of the Cleaverville Formation, in a similar stratigraphic position to the deposits seen in the Shay Gap and Sunrise Hill deposits to the west. The Cleaverville Formation overlies an intrusive complex of Archaean granite to the south. To the north, it is succeeded by a shale/siltstone member. The regional geology is shown on Figure 3.1.
The Yarrie Y3 deposit strikes east-west and outcrops for a strike length of approximately 1,000 metres. The high-grade haematite ore is flat-lying and is covered by lateritic capping material up to 20 metres thick.
The western Y2 deposit (a deep extension of the Y3 deposit) strikes northeast-southwest and is covered by some 40-100 metres of overburden BIF. The ore in this area is bounded to the north by a fault and ore continues to depths of approximately 110 metres below the plain level. Figure 3.2 shows typical cross-sections of the Y2 and Y3 areas of the Yarrie deposit.
3.3 TOPOGRAPHY
The project area is located in an area of low, rocky hills, plateaux and ridges interspersed with wide sandy plains and occasional small claypans. Numerous small, ephemeral, sandy-bedded creeks dissect the area.
Cundaline Ridge, a long, low line of hills with elevations of up to 261m AHD, follows the route of the proposed railway extension. In the mine area, two large plateaux, Yarrie Ridge and Callawa Ridge, are bordered by steep slopes and cliffs. The Callawa plateau contains the
Ah 1' e — , 1 I ND .. ..... __ , .. , .. .
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26 'R&d 2: 2km I SCALE H \\\ E 22 - 1 •, 1 YAPIE / Highly Sheared Mafic/Uitramaflc I I . .. \Y2f3.PIT Varie / 01 :::::Ile banded Iron FormatIon \ ARCHAEAN Red - 02Tt 04 05 06 09 10 11 12 i,/ 41 l5 . _16 17 is 1Q... 2O2L.-22 Interbedded with Chert .1 .; . ...4.._. 4.: ..Mundarifl.ya.,I Rge GAl Volcanics Mafic Sills i I - Pillow Basatts Dolerite — J 2d Poorly Sorted Clastic Sediments ie Wackes Quartzite Conglomerate c'-R1dge H I Eel Creek Formation - --( - PROTEROZOIC L... Shale Dolerite Sills 'Y. .- 261 I CRETACEOUS I I Sandstone Slltstone varrre / I f
AW TERTIARY Unconsolidated Alluvium TO RENT Sands, Conglomerates, Clays ,
ci
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DAMES & MOORE FIGURE 3.1 Base Plan supplied by BHP iron Ore. SE NW
+ + I
67M 4- :: 0 50 lOOm I I I 87rn 87m 87m 3m 99m 9 Y 3 + ± + + + + ± + + + + + + + + + + + 44550E section -
Stratipraphy Ore types BHP ron Ore (Goldsworthy) Ltd. r7ZT1 twejve Latertte - 50% Fe SF Cruetel ore 50 - 60% Fe TDrilh.le Hh grade ore 4 ocatIon YARRIE 2 / 3 Wdstone / quartzlio typ4caly 66% Fe Granite Depth (m) Typical Cross — Sections BI-F06 Aug. 1992
FIGURE 3.2 - 19 -
highest point in the project area at 289m AHD. Within and between the ridges and plateaux, small and large gaps (including Shay Gap, Cundaline Gap, Kimberley Gap and Kennedy Gap) permit the passage of creeks, roads and rail lines. The elevation of the gaps and sandplains is generally about 100-120m AHD. Views of the topography of the project area are shown on Plates 1, 2 and 3.
The project area is bordered to the north and east by the broad sandplains of the Great Sandy Desert and to the south by the floodplain of the De Grey River.
3.4 SOILS AND ERODIBILITY
The soils of the project area are derived from the erosion of an Archaean sedimentary plateau, of which the ridges and plateaux are remnants. The soils range from shallow, skeletal, rocky soils on the plateaux to sandy alluvial soils on the sandplains and creeklines. Occasional small claypans occur in the project area. The soils are mostly coloured a deep red due to staining by a relatively high iron content.
The erosion potential of the upland soils is low due to their rocky nature. The sandy soils of the lowlands would be highly erodible by water if disturbed. The potential for wind erosion of both types of soil appears to be low.
3.5 HYDROLOGY
3.5.1 Regional Hydrology
The surface drainage of the project area originates as small, ill-defined creeklines on the upland areas. Upon reaching the sandplains these drainage lines may converge to form sandy creekbeds or terminate in broad outwash fans. Stream flow in the area is highly ephemeral and for most of the year the creeks are dry, except for occasional poois formed in gullies on the ridges. Large stream flows are associated with high-intensity rainfall. On some of the ridges there are permanent pools which have traditionally been used by Aborigines.
The largest creek in the project area is Eel Creek, an ephemeral watercourse whose main bed is about 50m wide. Eel Creek joins the De Grey River, a major inland watercourse, about 8km south of the proposed mine site. Like the smaller creeks, the De Grey River flows only intermittently (typically for about 2 months of the year), although it does contain some semi-
4 N 0 R T H Possible Office! Overburden Village Workshop Site Y2 Pit Crusher Dump I
- £ • . - ••i'-'.::s - -: — e .... - -_- - 2 - -. - .*.,
)c ,
VIEW FROM CALLAWA RIDGE, LOOKING NORTH TO YARRIE PLATE 2
4 W E S T Mundarinya Callawa Ridge Ridge
Village .-.------.. -*T PRO -
VIEW OF RAILWAY ROUTE, LOOKING SOUTH-WEST FROM YARRIE PLATE 3 - 20 -
permanent pools. The only other significant watercourse in the project area is Cooneeina Creek, an ephemeral creek that drains south through Shay Gap, at the western end of Cundaline Ridge.
Groundwater occurs in the region mainly within two distinct hydrogeological units. One is the narrow strips of alluvial deposits of the major drainage channels such as the De Grey River and Eel Creek. The other is the Archaean bedrock that underlies the region and forms the ranges and ridges such as Cundaline, Yarrie and Callawa. The groundwater in the area, both in fractured bedrock and alluvium, would be recharged by inifitration of summer rainfall, particularly along major drainage lines.
The groundwater flow would be expected to generally follow the direction of surface drainage, except where controlled by local geological structures. The most active groundwater system would be that within the alluvium of the De Grey River.
The Archaean rocks would be expected to have low to moderate permeability associated with discontinuities and fractures. Experience at Mount Goldsworthy suggests that the permeability may be highly directional. The banded iron formations may form small but significant aquifers.
3.5.2 Local Hydrology
The banded iron formations of the Pilbara tend to form good aquifers with water of potable or near-potable quality. In addition, the major drainage lines such as the De Grey River and Eel Creek contain substantial alluvial aquifers. The hydrogeology of the Eel Creek aquifer is shown on Figure 3.3.
From exploratory drilling carried out in 1992 (AGC, 1992b), it appears that the Yarrie plateau contains a perched aquifer confined by the granite and mudstone that underlie the ore body. The groundwater table in the plateau lies at 170m AHD, approximately lOOm below the ground surface at the top of the plateau. This is considerably higher than the water table in the plains, which lies at hOrn AHD. A conceptual illustration of the hydrogeology of the Yarrie ore body is shown on Figure 3.4.
Steep hydraulic gradients are expected away from the perched aquifer of the plateau to the surrounding plains. A preferential flow path may exist, most likely to the south-west along the "keel" of the deposit or to the west across the normal fault.
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a69IIIA aIJJe,I 8II1ISSOd \ - 0 JV U0fle5!SeAuI Aiddri jaeM "' :1 AjejuewipeS Mo9joie JI ...... •AONVS eje6uol3 JO UOX xoJdd I I
IVJ.&D /dPAQtIE'.ct Iii I I ; Rainfall \,
'I
Recharge I Fractured, Brecciated
Graniod + V 7OmRLI iilOm - - I_'J VV I I i i auiI., r -1- 7 y ' 2(2 Perched Y 2 conductivity + + / + aquifer Al' + 118m Section 06 + + +,. Water table + + + + 4 + - - - + ± + +# 169 /71 11OmRL + + Steep Hydraulic + L v______gradient / 50 100m
Stratigraphy Ore types 3HP Iron )re (Goidsworthy) Ltd. Mat Ic Intrusive Laterite < 60% Fe BIF Crustal ore 50 - 60% Fe TD.11h.te 'S1Yarrie ; High grade ore 3LocatIon YARRIE 2 Mudtone/ quartzite typicaly 88% Fe ran1te Depth (n) Schematic Hydrogeological Model BI-P07 Oct. 1992 FIGURE 3.4 - 21 -
Seasonal rainfall would easily penetrate the highly-permeable surface soils and banded iron formation (BIF) of the plateau. The rainwater would be retarded by the granite/mudstone basement of the ore body. The resulting steep hydraulic gradient would allow for a continual recharging of the perched aquifer with a very slow discharge into the regional water table.
Being recharged only by rainfall, the water contained in the perched aquifer is soft (65mg/i CaCO3), near-neutral (pH 6.7) and of low salinity (300mg/I TDS) (AGC, 1992b).
3.5.3 Water Resources
Water supplies for the project will preferentially be obtained from bores drilled adjacent to the Yarrie ore body, augmented if necessary from a borefield in the Eel Creek aquifer. Present indications are that the Eel Creek aquifer contains more than adequate resources to supply the anticipated demand of 1,000klJday, but the potability of the aquifer has not yet been proved. This is currently under investigation. Other hydrogeological investigations now underway should indicate whether the perched aquifer of the Yarrie plateau is capable of yielding enough water to satisfy the requirements of the project without drawing on the Eel Creek resource.
3.6 CLIMATE
The Pilbara region has a dry tropical climate. Very high temperatures are common (particularly inland) during the summer months. Rainfall throughout the region shows a strong summer maximum with very dry conditions during the late winter and spring. Winds are predominantly from the south-east, with sea breezes occurring along the coast.
There are four specific weather phenomena which are of greatest importance to the region. The summer monsoon brings most of the annual rainfall to the region. Its influence is strongest in the northern parts of the Pilbara and decreases to the south. Much of this rain comes from tropical cyclones, which are also associated with damaging winds and flooding.
During the winter months, development or intensification of anticyclones over southern Western Australia and South Australia may produce strong easterly winds over parts of the North West. Also during winter, major cloud bands may develop which extend from off the north-west coast across the continent and bring significant rain to the North West and the interior of the country. - 22 -
Climatic data for Goldsworthy are available from the Bureau of Meteorology for the period since 1966 (Bureau of Meteorology, 1988) and are the nearest data available for Shay Gap and Yarrie.
Average daily maximum temperatures in Goldsworthy range from 28.1°C in July to 40.3°C in December. Average daily minima range from 14.3°C in July to 26.4°C in January. Goldsworthy's annual rainfall averages 329mm, with the highest rainfall occurring in February and the lowest occurring in October. There are, on average, 36 rain days per year, ranging from an average of 7 in January and 8 in February to none in October. Evaporation exceeds average rainfall in all months and may exceed total rainfall by as much as 2500mmlyear. Climatic data for Goldsworthy are summarised in Table 3.1.
TABLE 3.1
CLIMATIC AVERAGES - GOLDSWORTHY
Temperature Rainfall Month Mean Low (°C) Mean High (°C) Average Average No. of Rainfall (mm) Rain Days January 26.4 39.6 76 7 February 26.1 38.8 95 8 March 26.0 38.6 51 6 April 23.1 36.4 16 2 May 19.5 31.6 25 3 June 16.3 28.4 17 2 July 14.3 28.1 12 1 August 16.5 30.6 4 1 September 18.8 34.2 2 1 October 21.4 37.5 1 0 November 23.6 39.5 3 1 December 25.3 40.3 27 4
A result of the extremes of climate experienced at Yarrie is that the flora and fauna of the region tend to be hardy, adapted to harsh, and conditions and to be opportunistic breeders. Fauna are often nomadic and many are able to survive without access to liquid water. - 23 -
3.7 VEGETATION AND FLORA
Vegetation and flora surveys were carried out in the project area on 12 and 13 August and 1 to 5 October 1992. A full report of these surveys is presented in Appendix B.
The project area lies in the extreme north of the Fortescue Botanical District with the possible exception of the far northern extremity of the proposed power line route, which may just touch the Canning Botanical District. More specifically, the project area is within the George Range vegetation system or physiographic unit.
The characteristic vegetation of this system is snappy gum and bloodwood tree steppe on higher, rocky areas, with spinifex hummock grasslands and shrub steppe on slopes, plains and broad valleys. Trees and, to a lesser extent, shrubs are mostly sparse. Minor drainage lines often have thickets of acacias and other shrubs, while the larger watercourses have fringing belts of eucalypt woodland, sometimes with Cadjeput and other trees.
Overall, the vegetation of the project area is typical of the northern Pilbara. The vegetation associations and most of the species present are widespread in surrounding areas or occur over a broad range.
Two wetlands exist in the project area. One is a spring and permanent stream with a prominent low forest of acacias and a shrub understorey near the western end of the proposed railway extension, next to overburden storage sites associated with the Shay Gap mine pit. The vegetation of the site is far from pristine as a result of intensive trampling and feeding by cattle, feral donkeys and horses. The ground of the site would formerly have carried a dense grass cover and the forest would have been more diverse; today only the longer-lived trees are present.
The other wetland is a shallow seasonal pool in the eastern part of the railway route which would, when wet, contain the Nardoo Fern and ephemeral grasses. This pool was dry at the time of the 1992 surveys.
None of the species identified during the flora surveys has been classified by the Department of Conservation and Land Management (CALM) as Declared Rare Flora or Priority Flora. Several species have local conservation significance, being recorded in only one or two locations in the project area. Most of these are located in areas that will not be disturbed. The only one - 24 -
that may be significantly disturbed is Eucalyptus odontocarpa, which was found only on the Yarrie plateau. The degree of disturbance to this species will be moderate, and the species is widely-distributed in surrounding areas.
3.8 FAUNA
3.8.1 Introduction
A field assessment of the fauna at Yarrie was carried out between 2 and 5 October 1992. A full report of the survey, including lists of species recorded or expected to occur in the project area, is presented in Appendix C.
3.8.2 Habitats
The habitats of the project area are mostly typical of the Pilbara, although lacking in the shrublands that are typically found further to the south and west. Four broad categories of habitat can be recognised in the project area:
creeks and claypans - all those which have a clearly-defined belt of fringing vegetation; hills and stony rises - all hills, cliff faces, scree slopes and low-lying rocky areas; spinifex plains - all valley floor habitats on sandy, loamy and stony soils; and Great Sandy Desert - possibly occupying a very small section of the proposed power line route north of the Shay Gap township.
3.8.3 Vertebrate Fauna
The faunal assemblage observed during the survey included 35 birds, 5 mammals, 1 amphibian and 7 reptiles. Amongst the mammals, the Ghost Bat and Pebble-mound Mouse were notable observations. These are discussed below. The birds, amphibians and reptiles observed are all common and widespread.
The absence of shrublands of any magnitude reduces the number of expected species, especially of small insectivorous birds. The close proximity of the Great Sandy Desert necessitates the inclusion of a number of species (mostly reptiles) not present in the typical Pilbara fauna. - 25 -
3.8.4 Rare Fauna
Appendix C lists a number of species protected under the Wildlife Conservation Act 1950. These species are gazetted under two schedules. Schedule 1 species are described as "fauna that are likely to become extinct or are rare". Schedule 2 species are those described as being "in need of special protection".
Evidence of two Schedule 1 species was found in the project area; the Pebble-mound Mouse and the Bilby.
A large number of mound-nests of the Pebble-mound Mouse (Pseudomys chapmani) were observed in an area immediately to the east of the proposed mine pit. Approximately 50% of these mounds appeared to be active, with obvious, well-maintained burrow entrances. The density of mounds was high, with as little as 30 metres separation between mounds in some cases. No confirmed observations of mounds have been made in the area of the proposed mine pit or other development areas, and no mounds were observed in those areas during the 1992 fauna survey.
A disused burrow system possibly belonging to the Bilby or Rabbit-eared Bandicoot (Macrotis lagotis) was found in friable, loamy soil adjacent to a creekbed in the south-eastern section of the proposed railway alignment. Since European settlement, the Bilby has suffered a 50-90% reduction in range (Kennedy, 1990). Several Bilbies have been sighted around Shay Gap in recent years. Two road kill specimens have been collected by BHP personnel in the last 18 months and one of these was sent to the W.A. Museum for positive identification.
Other Schedule 1 fauna which could possibly be present in the project area are the Mulgara (Dasycerus cristicauda), the Lesser Stick-nest Rat (Leporillus apicalis) and the Grey Falcon (Falco hypoleucos). The Mulgara is a desert species which could be present only at or near the far northern part of the power line route. The Lesser Stick-nest Rat formerly ranged over much of central Australia but is now believed to be extinct. None of the characteristic bitumen-like nests of the species were observed in the caves and breakaways of the project area. The Grey Falcon is distributed very widely but sparsely throughout inland Australia.
One Schedule 2 species, the Pilbara Rock Python (Morelia olivaceus barroni), was observed in a rock pooi in a gully on the Callawa plateau. The preferred habitat of this species is near pools on watercourses. With the apparent scarcity of pools in the project area, it would probably be uncommon. - 26 -
Other Schedule 2 species that might be present are the Peregrine Falcon (Falco peregrinus), the Long-tailed Dunnart (Sminthopsis longicaudata) and the Woma Python (Aspidites ramsayi). These species are discussed in detail in Appendix C.
A single, mummified specimen of the Ghost Bat (Macroderma gigas) was found on a barbed- wire fence near the proposed rail loadout loop. This species is protected under the International Union for the Conservation of Nature (IUCN) and its inclusion in the Western Australian "Reserve" list (Schedule 2) is awaiting ministerial approval. This species would probably utilise the many roosting caves located in cliff faces in and near the study area.
Other notable but ungazetted species that might be present are Rothschild's Rock-wallaby (Petrogal.e rothschildi) and the Orange Horseshoe-bat (Rhinonicteris aurantius). The habitats in the project area are marginal for both of these species, as discussed in Appendix C.
3.8.5 Feral Fauna
Two groups of Donkeys, each containing six individuals, were observed. Judging by the number of tracks and droppings seen in the area, the total local population must be substantially higher than the twelve animals observed. Other feral species that may occur in the project area are cats, foxes, house mice, goats, horses and camels. No obvious signs of any of these species were apparent during the survey and their numbers may be low because of successive poor seasons experienced in the area.
3.9 ABORIGINAL HERITAGE
Before the advent of European pastoralism in the 1860s, Aborigines inhabited the Pilbara for at least 20,000 years. The Yarrie project lies within the traditional lands of the Nyamal- speaking people, whose territory was centred on the Oakover, lower Nullagine and central De Grey Rivers.
Aboriginal people in the northern Pilbara were essentially "river people", whose lives were centred around the major river systems such as the De Grey. They were not confined to the rivers, however, and mythological sites and the remains of campsites and stone quarries are scattered across the Pilbara, albeit concentrated most densely near permanent pools associated with rivers. - 27 -
Archaeological and ethnographic surveys were conducted in the Yarrie mining area in 1988, 1991 and 1992 (O'Connor and Quartermaine, 1991, 1992). A number of archaeological and ethnographic sites have been identified in the Yarrie, Callawa, Mundarinya and Cundaline areas. Copies of the archaeological and ethnographic survey reports have been lodged with the Aboriginal Sites Department of the Western Australian Museum.
The only Aboriginal community in the vicinity of Yarrie is the outstation of Mijijimia which is located about 100km east of the project. There are about 100 residents, who are members of the Nomads Group. Callawa Station has been deserted for a number of years and there are no Aborigines resident at Yarrie Station.
3.10 EUROPEAN HERITAGE
There are believed to be no historic European structures or European heritage values associated with the project area.
3.11 EXISTING LAND USE
3.11.1 Pastoral Leases
Four pastoral leases exist in the vicinity of the project area: Muccan, Yarrie, Callawa and Warrawagine (Figure 2.1). The proposed mine site is situated at about the junction of the Yarrie, Callawa and Warrawagine leases, although it does not impinge on the Warrawagine lease. The rail and access road routes traverse the Yarrie and Muccan leases. BHP has held, and will continue to hold, consultations with the owners or managers of all pastoral leases affected by the proposal.
3.11.2 Tourism and Sightseeing
The project area is relatively remote and of low significance to tourists or sightseers as there are similar landforms in the local area. Being located on both an existing mining lease and a pastoral lease, the project area is not readily accessible to the general public. - 28 -
4.0 ENVIRONMENTAL IMPACT ASSESSMENT
BHP has identified a number of potential impacts of the project on the environment. In each case, management strategies have been identified to avoid or minimise the adverse impacts. The potential impacts of the project are discussed in the following subsections. Management and monitoring strategies for the potential impacts are described in section 5.0.
4.1 LANDFORMS
4.1.1 Construction Earthworks
Changes to the topography of the project area will result from earthworks required to prepare the principle development sites including the mine pit, overburden storage site, village, railway line, access roads, airstrip and mine buildings. Construction earthworks will affect approximately 354 hectares. The impacts will be largely confined to the immediate development sites. The impacts will vary from short to long term. Some disturbances will be rehabilitated following construction while others, such as the mine pit and railway line, will be effectively permanent.
Mining of ore from the Yarrie ore body will result in the formation of a large mine pit. Most overburden from the mining operation will be deposited in a crescent-shaped gully to the south of the mine pit (Plate 1). In time, this gully will be filled in and will come to resemble an extension of the plateau. Some of the overburden will be backfihled into the Y3 pit.
4.1.2 Borrow Pits
Borrow pits will be required for construction materials at the mine site, airstrip and along the rail spur. The location and size of these pits will be largely determined by the availability of suitable construction material and the location where it is required.
Apart from their visual impact, borrow pits provide sites for temporary water storage, which may encourage mosquito breeding. Use of these pits as watering points by animals may increase the risk of deaths due to road and rail accidents. - 29 -
4.1.3 Erosion
The sandplain soils of the project area are highly erodible when disturbed. However, the low slopes in these areas will reduce the incidence 'of erosion. Erosion could occur:
on roads and tracks; around the village, workshop and office areas; and at creek crossings and culverts on the railway line.
The rocky soils of the upland areas are not expected to require any special erosion control measures. Likewise, the overburden site is not expected to erode significantly in the short term due to its coarse, rocky nature. Rehabilitation will ensure its long-term stability.
4.2 SURFACE HYDROLOGY
Water Discharge The water table level in the area of the mine pit is currently at 170m AHD. By the time mining in Y2 has reached this level, the water table is likely to have been drawn down considerably by the abstraction of water for domestic and mine uses. Eventually, however, the mine pit is likely to reach the water table. When that happens, dewatering of the pit may be required.
The required rate of dewatering will depend on the amount of pre-existing drawdown but is unlikely to be more than a few hundred cubic metres per day. Most or all of this water will be used for dust suppression and other mine-related uses. Any excess will be discharged to a natural water course and allowed to seek its way to Eel Creek. Depending on the dewatering method used (bores or in-pit sump), this water may contain high loads of suspended solids. The quality of the water will otherwise be high, as described in Section 3.5.3. The exact quantity of water to be discharged cannot yet be determined but is not expected to be suffluent to create surface flow, large pools or significant raising of the water table in Eel Creek. It is expected that the water will only reach Eel Creek as surface flow during high rainfall periods.
Railway Line The railway line has the potential to interrupt the natural surface flow of water where it crosses drainage lines. This could adversely affect vegetation downslope of the railway. - 30 -
In 1986, Mount Newman Mining Co. Pty Limited commissioned a detailed study (Natural Systems Research Pty Ltd, 1986) of a section of the Newman-Port Hedland Railway to investigate the effects of that railway on the surface drainage of the area and the resulting impacts on vegetation. The study found that, of the three main vegetation communities present near the railway (eucalypt woodland, spinifex hummock grassland and Mulga scrub), only the Mulga (Acacia aneura) scrub was affected by changes in drainage caused by the railway. Other species of Acacia were not affected. Furthermore, the effects on Mulga were variable and poorly correlated with soil types, drainage characteristics and other factors. Few instances were found where Mulga decline was clearly related to shadowing effects of the railway. These instances tended to occur in areas of gentle gradient with no defined watercourses, where surface drainage consisted of overland sheet flow. The major impact of the railway in these areas appeared to be in discouraging regeneration of Mulga from seedlings where stands of the species had been degraded by other factors such as grazing by stock, fence post cutting, wind throw or other physical disturbance.
From the findings of the above study, it can be concluded that the shadowing effect of the Yarrie railway extension will have little impact on the vegetation communities of the project area. Mulga does not occur in the area and the other vegetation types present (mainly spinifex grassland and tree/shrub steppe) are not susceptible to shadowing effects. This will be aided by the location of the railway line which, for most of its length, runs through or adjacent to terrain which has relatively steep gradients, and where drainage channels tend to be well- defined and free-flowing.
4.3 HYDROGEOLOGY
The hydrogeology of the project area may be affected by abstraction of water from bores near the mine pit or in the Eel Creek aquifer and, in later years, by the dewatering of the mine pit. Hydrogeological studies (AGC, 1992b) have shown that the water table in the Yarrie plateau is perched about 60m above that of the surrounding plains and is partially confined by the mudstone and granite that underlie the ore body. Pit dewatering may be required during the latter years of the project when mining has reached the local water table. However, the effect of this on the regional aquifer will be confined to a very small reduction in recharge from the perched aquifer. The effect of this reduced recharge is expected to be insignificant.
Excessive drawdown of the Eel Creek aquifer due to abstraction for water supply could have adverse effects on the phreatophytic (groundwater-dependent) vegetation, such as some - 31 - eucalypts, in the creekbed. However, since the Eel Creek aquifer is intended to play only a minor role in providing water supplies, the degree of drawdown in the aquifer is likely to be within acceptable limits. There are no permanent or semi-permanent pools in Eel Creek to be affected by drawdown.
After the cessation of mining, the mined-out Y2 pit will slowly fill with groundwater to a level between the regional groundwater level (1 lOm AHD) and the perched groundwater level of the plateau (170m AHD). The final water level in the pit is unclear at present and is expected to take many years to be attained.
The salinity of the perched aquifer on the Yarrie plateau is about 300mg/i TDS, as measured in the Y2 Bore at the southern end of the pit area (Figure 3.3). As this water seeps into the abandoned pit, evaporation will cause the salinity of the water in the pit to slowly increase. A similar situation exists in the Mount Goldsworthy pit, where mining and dewatering ceased in 1982.
Eventually, over hundreds or thousands of years, a brine may form in the Y2 pit. The density of the brine may be sufficient to drive saline water out of the base of the pit, against the local hydraulic gradient, into the regional aquifer. The resulting saline plume would probably move south-west through the Eel Creek aquifer at a rate of between 0.1 and 2.0 metres per year until it reached the De Grey River aquifer. It would take between 5,000 and 100,000 years for the plume to reach the De Grey River, where its effect would be to increase the salinity of the De Grey River alluvial aquifer.
4.4 FLORA AND FAUNA
The potential impacts on flora and fauna resulting from the construction and operation of the project are:
loss of vegetation and fauna habitat; changes to drainage; barrier effects; disturbance due to noise; and 0 partitioning of faunal territories. - 32 -
4.4.1 Impacts on Flora
The construction of the railway will damage plant communities along its length. However, the area of vegetation cleared will be small in comparison to the floristic units present in the general area, and all the species affected are well represented in surrounding areas.
The main areas of concern to both plant and animal communities will be associated with creek crossings. As moisture is scarce in this and environment, the main drainage channels of the area are foci of both plant and animal diversity. In general, damage to significant creeks will be limited to a small area of physical disturbance at the site of the actual crossing.
Destruction of plant communities will be complete throughout the mining and overburden storage areas. Considerable disturbance to plant communities will also occur on the sites of infrastructure works. The vegetation to be cleared is not unique and is repeated on similar hill systems in the general area. The area affected will be small in comparison to the floristic units present in the region, and all of the plant species affected are well represented in the surrounding area.
Weeds such as Ruby Dock (Rumex sp.), Kapok (Aerva javanica) and Buffel Grass (Cenchrus diliaris) are proven survivors in the Pilbara. These weeds tend to invade areas of disturbed ground and can displace or impede the regeneration of native species. Roads and railway lines can act as conduits for weed invasion. There is no significant weed invasion in the project area at present. Management will be required to ensure that the potential for weed invasion is minimised and that any infestations detected are dealt with effectively.
4.4.2 Impacts on Fauna
Disturbance The fauna of the project area, both native and introduced, can be broadly described as being of two types: mobile (widely-dispersing) and non-mobile (poorly dispersing). Mobile species include kangaroos, wallabies, most birds and flying insects. Non-mobile species include those which are unable to move far, such as snails, and those which are able to move but are unwilling to do so for territorial or other reasons (such as some small marsupials), or which move only slowly (such as lizards). - 33 -
The more mobile species will simply move out of the area when disturbance begins. Many, such as some birds, will return despite ongoing disturbance. Many others will return following decommissioning. The small size of the area of disturbance will ensure that recruitment from surrounding areas will be rapid once the project ends.
The non-mobile and poorly mobile species occupying sites of disturbance will be destroyed. Once the disturbance ends, these species will recolonise the disturbed areas from surrounding areas, at a slower rate than for the highly-mobile species.
Railway Line Some small mammals and reptiles will be unable or unwilling to cross the railway line and may, as a result, suffer loss of territory due to partitioning. Others, however, will benefit from annexation of the portions of territories thus abandoned. Overall, the construction of the railway will lead to a loss of territory and possibly the deaths of some individual animals. As the small terrestrial animals in the area generally do not require regular access to surface water, the obstacle presented by the railway line will not be critical in most cases. The culverts provided on drainage crossings will enable some small animals to cross under the railway line.
The degree of interference by the railway line to the movement of Euros is likely to be minor. Numerous well-used Euro tracks were observed on the sides of the Mount Goldsworthy overburden storage areas, which average 32m high. On this evidence, Euros do not appear to regard barren rock slopes as a barrier to movement.
The animals of the area are not expected to be affected by train noise, which will be intermittent and short-lived. Euros and other animals crossing the line may occasionally be hit by trains. This is not expected to be a significant impact but could be exacerbated if borrow pits containing water were left in place near the roads or railway line.
Loss of Habitat The principal impact on fauna from the mining of the plateau will be loss of habitat. The main - species affected will be the Euro. This is a common and abundant species throughout the Pilbara. Other upland areas in the vicinity of the development, which will not be mined, contain similar habitat and are expected to sustain similar population densities. The grassy plain which is the proposed site for placement of overburden will become a new hill. In this sense, one habitat sequence will be exchanged for another and many plant and animal species will eventually return. - 34 -
Gullies and caves in the mining area provide niches for amphibians, snakes and bats. None of these ,species are likely to suffer any significant loss of genetic diversity due to the local extinctions caused by mining. Numerous mounds associated with the Pebble-mound Mouse occur in spinifex hummock grasslands on the plateau adjacent to the mining area. Up to 50% of these mounds are believed to be active (Section 3.8.4). There could therefore be a large population of Pebble-mound Mice in the area. None of the known mounds are located within the mine pit area or in other areas likely to be significantly disturbed by the project. Although little is currently known about this species, mounds are widespread throughout much of the Pilbara region.
4.4.3 Impact on Wetlands
The railway line will pass close to a small permanent spring just west of Cooneeina Creek, next to the Shay Gap overburden storage sites. The spring and its associated vegetation thicket will not be physically disturbed by the railway extension. The surroundings of the spring are heavily degraded by the presence of an apparently permanent population of cattle.
Another small, ephemeral wetland, which was dry at the time of the 1992 field surveys, exists near the eastern end of the railway route. This wetland is already crossed by the access road to Yarrie and will be crossed by the railway line. The wetland supports the Nardoo fern (Marsilea sp.) and several species of ephemeral grasses, which do not occur elsewhere in the project area. These species are, however, all widespread across the Pilbara region. The construction of the railway line should affect less than 5% of its area.
4.5 NOISE AND DUST
Noise Noise will be generated by blasting and the operation of mine machinery, trains and vehicles. As well as its effects in terms of annoyance and sleep disturbance, noise has occupational safety significance for operators of machinery.
Blasting will occur regularly and has the potential to create disturbance at the village. Blasting noise is intermittent and very short-lived. Village residents will generally be accustomed to the noise and will experience little or no inconvenience. After the initial overburden removal stage, when blasting is occurring at deeper levels in the pit, blasting noise levels outside the pit will be much reduced.
- 35 -
Trains will operate several times a day in each direction. The closest approach of the railway line to the village will be about 3km. Investigations carried out at Newman by BHP (1987) indicate that, at this distance, train noise will have negligible effects on the village, even at night. No management of this impact is necessary.
Vehicles, the crusher and other mine equipment will create a continuous, low-level background noise. This is expected to have negligible effect and no management is therefore necessary.
Dust Airborne dust will be generated from a number of sources including blasting, excavation, crushing, train loading and movement of vehicles on the unsealed roads of the project area. Dust has occupational safety as well as nuisance significance. The village will be located about three kilometres north-west of the mine and may experience periodic dust impacts, particularly following blasts, during unfavourable wind conditions.
4.6 HAZARDOUS MATERIALS
The development and operation of the project will necessitate the use of a wide range of products which may be termed "hazardous materials". These substances include fuels, lubricants, detergents, explosives and paints. If allowed to escape, many of these materials could cause atmospheric, soil or water contamination and could pose a risk to the health of humans and the ecosystem.
4.7 WASTE PRODUCTS
The mine will generate several types of non-toxic waste, including scrap metal, tyres, wood, paper and domestic solid and liquid waste. While not hazardous, these wastes could cause visual pollution and some environmental damage if not disposed of properly.
4.8 FIRE
Fire is a common phenomenon in the Pilbara. Lightning strikes cause many fires across the region. In areas close to settlements and roads, fires may also be caused by campfires, cigarette butts and broken glass, or deliberately lit. Historically, Aborigines used fire as a tool for hunting and to encourage the growth of grasses which would attract game. The project area therefore has a long history of fire and both the vegetation and fauna are well-adapted to a cycle of burning and regrowth. The proposed developments at Yarrie will not significantly increase or decrease the risk or incidence of fire in the project area. - 36 -
5.0 ENVIRONMENTAL MANAGEMENT AND MONITORING PROGRA1,1ME
5.1 LANDFORMS
5.1.1 Construction Earthworks
Objective: To minimise disturbance to the existing topography.
Management: Only the minimum areas required for construction will be disturbed. Topsoil to a depth of about 15cm will be stripped and stockpiled, where practicable, prior to earthmoving. Once construction is completed, all areas no longer required for the operation of the facility will be recontoured, topsoiled (if topsoil is available) and ripped. If necessary, disturbed areas will be seeded with local species.
Monitoring: Close supervision of contractors by BHP will ensure conformity with the above guidelines. No contractor will vacate a site until it has been rehabilitated to the satisfaction of BHP. Monitoring of rehabilitated areas will continue until the vegetation is seen to be progressing towards a condition approaching that which existed before disturbance.
5.1.2 Borrow Pits
Objective: To minimise the physical impact of borrow pits on the environment.
Management: Borrow pits for all construction materials will be selected and operated to minimise erosion and land disturbance. Where possible, pits will be located where they are not visible from the village or access roads. The BHP-Newman Guidelines and Objectives for Borrow Pit Development and Rehabilitation (Appendix D) will be applied.
5.1.3 Erosion
Objective: To minimise wind and water erosion due to disturbance by mining. - 37 -
Management: Erosion around roads and building areas will be controlled by minimisation of clearing, rehabilitation, proper drainage and bunding where necessary. Erosion at creek crossings and culverts will be minimised by careful design and the use of rock armouring.
Monitoring: Regular visual inspections will be made to evaluate the effectiveness of erosion control measures and to detect and repair any erosion damage which does occur.
5.2 SURFACE HYDROLOGY
5.2.1 Pit Dewatering
Objective: To ensure that the volume or quality of water discharged from the mine pit does not result in unacceptable effects on the environment.
Management: While mining below the water table and dewatering are taking place, the quantity of water pumped from the pit or dewatering bores will be managed at the minimum necessary to achieve adequate dewatering. As much as possible of the water will be used for mining-related activities such as dust suppression.
Water released to the environment will, if necessary, be discharged via settling ponds to ensure that the water finally released meets the Australian & New Zealand Environment & Conservation Council's recommended limits for suspended solids in aquatic ecosystems.
Runoff from areas susceptible to low-level contamination by hydrocarbons or other materials (such as workshops, fuelling bays, etc.) will be drained to holding ponds to allow for evaporation and decomposition of contaminants.
Licences will be applied for under Section V of the Environmental Protection Act 1986 for all water discharges.
Monitoring: The dewatering rate and the degree of drawdown will be constantly monitored. Regular samples of any discharged water will be collected and analysed for Suspended Solids and other important water quality parameters. - 38 -
5.2.2 Effects of Railway Line
Objective: To minimise adverse impacts of the railway embankment on the surface hydrology and vegetation of the project area.
Management: The design of the railway will incorporate extensive culverting to ensure that disruption and shadowing effects on surface drainage are kept to a minimum. Training of drainage channels will be carried out in some areas, as described in Section 2.5, to further minimise effects on drainage.
Monitoring: BHP will establish a programme to evaluate the health of vegetation downslope of the railway embankment. The programme will involve setting up a number of transects in areas considered to be susceptible to shadowing from the railway line. Annual surveys will be conducted of these transects to record vegetation health and diversity parameters such as canopy cover, average foliage density and species composition. If any adverse impacts are revealed by this monitoring, BHP will take steps as necessary to mitigate those impacts.
5.3 HYDROGEOLOGY
5.3.1 Drawdown of Groundwater
Objective: To ensure that groundwater abstraction and pit dewatering do not result in unacceptable drawdown effects on vegetation in the Eel Creek system.
Management: The abstraction of water from the Eel Creek aquifer and from the mine pit will be maintained at the minimum necessary to supply project water and pit dewatering requirements.
Monitoring: The rate of abstraction from the pit and the Eel Creek aquifer will be constantly monitored and adjusted to the lowest possible level. Groundwater levels and quality in selected bores will be regularly checked to detect drawdown and water quality changes that may indicate overpumping. If significant drawdown in the Eel Creek aquifer does occur, the health of phreatophytic (groundwater- - dependent) vegetation such as eucalypts in Eel Creek will be monitored to detect any deaths that may be due to drawdown and action will be taken to - ameliorate any impacts. - 39 -
5.3.2 Salinity Build-up in Y2 Pit
Objective: To minimise the build-up of salinity in the decommissioned Yarrie Y2 pit and the potential effects of such an increase on the water quality of the regional aquifer.
Management: Based on the results of consultants' investigations, BHP does not believe that any specific management of this issue is necessary or practical at this stage. It would be theoretically possible for the Y2 pit to be filled after mining, either by backfilling with overburden or by battering the pit walls, to a level above the water table. This would prevent the formation of a permanent water body in the pit and consequent salinity buildup. However, these alternatives are impractical because:
the cost of moving the large quantity of overburden required (estimated at 25 million tonnes) would make the entire project uneconomic; and to batter the slopes sufficiently to generate enough backfill, the area of the pit would have to be increased by about 25%, thereby substantially increasing the area of ground disturbance. The cost of this option would also be prohibitive, due to the high cost of drilling and blasting.
Monitoring: BHP will continue to monitor the water in the Mount Goldsworthy pit for several years to provide data on which to base more precise predictions of future salinity trends. The results of this monitoring will be used to determine the need and options for future management of salinity on the Yarrie Y2 pit. BHP will also continue hydrogeological studies, including drilling and modelling, to better defme the aquifers and groundwater flows in the project area.
5.4 FLORA
5.4.1 Railway Line
Objective: To minimise physical damage and shadowing effects of the railway line on vegetation. - 40 -
Management: The minimum area necessary will be disturbed for the construction of the railway line. Following construction, all areas no longer required will be rehabilitated. Particular care will be exercised to minimise damage to vegetation at creek crossings. Significant drainage crossings will be culverted to minimise impacts on normal drainage patterns. In general, as was discussed in Section 4.1.4, the vegetation types and landforms of the railway alignment are such that the shadowing effects of the railway line on vegetation are expected to be minimal.
I Monitoring: BHP will establish a programme to evaluate the health of vegetation downslope of the railway line (see Section 5.2.2).
5.4.2 Weeds
Objective: To ensure that weed species are not introduced or spread by the mining operation.
Management: No soil or fill material will be imported from outside the project area. If any existing weed infestations are found, borrow pits will not be located in the area of the infestation.
Monitoring: BHP will regularly inspect the vegetation alongside the railway line, access roads and other trafficked areas to detect weed invasion. If any nuisance weeds are discovered, appropriate physical or chemical control measures will be undertaken in consultation with the Department of Conservation and Land Management.
5.5 FAUNA
5.5.1 Railway Line and Road Kills
Objective: To minimise the incidence of railway and road kills so that animal populations are not threatened.
Management: Borrow pits will be located some distance from roads and the railway line wherever practical and will be rehabilitated when no longer required so as not - 41 -
to contain surface water for long periods after rainfall. These measures will prevent animals being attracted to near roads or the railway by water availability.
Monitoring: Visual monitoring of fauna deaths will be undertaken along the access roads and railway line. If excessive deaths are seen to be occurring, the reasons will be investigated and, where possible, appropriate corrective steps taken.
5.5.2 Pebble-mound Mouse
Objective: To avoid interference by the project to populations of the Pebble-mound Mouse and to collect data to assist in its proper management.
1 Management: Disturbance of areas containing Pebble-mound Mouse mounds will be avoided - as a matter of priority. The known area containing mounds is generally outside the area to be disturbed by the operation.
Monitoring: BHP will undertake a detailed survey of the distribution of Pebble-mound Mice and their mounds in the Yarrie area. This research will aim to provide mine management with a realistic set of management options to help conserve the species.
Techniques for studying the Pebble-mound Mouse are poorly researched and documented. The most recent known study was carried out at Marandoo in 1991 by Ninox Wildlife Consultants (K. Youngson, 1992 pers. comm.). The study concluded that, to achieve a valid population census, a trapping study involving a large number of mounds and traps would be required. A combination of fenced and unfenced mounds, box and pit traps was recommended.
BHP will liaise with the Department of Conservation and Land Management (CALM) and other wildlife researchers over the design and execution of an appropriate programme to investigate the Pebble-mound Mouse population in the area. BHP would be interested in a joint study with CALM, research - institutions or knowledgeable private consultants. - 42 -
5.5.3 Other Fauna Protection Measures
Objective: To minimise the overall impact of the project on fauna.
Management: To aid in the protection of fauna, pets (dogs and cats), firearms and - indiscriminate use of off-road vehicles will be prohibited in the project area.
Monitoring: Mine and village management will note the presence of any pets or firearms and will give instructions that they be removed. The use of off-road vehicles will be monitored and appropriate disciplinary action will be taken where necessary.
5.6 NOISE AND DUST
5.6.1 Noise
Objective: To avoid occupational and ambient noise impacts on workers and at the village.
Management: Blasting nuisance will be minimised by carrying out blasts only at specified times during daylight hours. Occupational noise levels will be managed by ensuring that all equipment is adequately soundproofed and that, where necessary, workers use appropriate hearing protection.
Monitoring: Periodic measurement of occupational noise levels will be carried out as required under the Works Approvals and Licences issued under Part V of the / Environmental Protection Act 1986.
5.6.2 Dust
Objective: To avoid or minimise adverse occupational and ambient dust impacts.
Management: Normal means of dust suppression, including watering by water trucks, water jets and sprays, will be used to control fugitive dust generation on roads and at the crusher, train loader and mine site. Occupational dust requirements will be met by means of dust suppression, sealing and airconditioning of vehicle cabins and other means as appropriate. - 43 -
Monitoring: Periodic occupational dust inspections will be carried out as required under - Works Approvals and Licences issued under Part V of the Environmental Protection Act 1986.
5.7 HAZARDOUS MATERIALS
Objective: To ensure the safe handling of all hazardous materials used on the site.
Management: The handling, use and disposal of these products will comply with all local and State regulations. Bulk fuel will be stored in above-ground tanks held in impermeable, bunded enclosures in accordance with Department of Minerals and Energy (DOME) requirements. Explosives will be stored in a magazine remote from accommodation facilities, workshops and the mine site, and above flood level. Care will be taken to ensure that nitrate-based explosives cannot escape into the environment.
BHP will adopt a formal Hazardous Materials Management Programme that will incorporate the following elements:
adoption of a formal policy statement; designation of responsibility for all elements of the programme; employee participation; training of personnel; dissemination of information; controls on purchasing and inventory; and 1• o environmental monitoring.
Monitoring: Regular atmospheric monitoring will be carried out as required under Works. Approvals and Licences issued under Part V of the Environmental Protection Act 1986. In addition, visual monitoring will be used to detect any leakage or spillage of liquid or solid hazardous substances.
5.8 OILY WASTES
Objective: To prevent the release of oils and hydrocarbon-contaminated water to the environment. - 44 -
Management: Used oils will be stored securely in drums or tanks and will be periodically removed by a licensed waste disposal contractor for recycling or disposal at a Council-approved site.
Runoff and wastewater from areas susceptible to hydrocarbon contamination, such as workshops and washdown bays, will be drained to holding/evaporation ponds, where sunlight and bacteria will decompose the hydrocarbons. Water containing hydrocarbon contamination will not be released to the environment.
Monitoring: Any surface water discharges from the project will be regularly sampled for the presence of hydrocarbons. Sampling of runoff will also be carried out during significant rainfall events. The holding/evaporation ponds will be checked regularly for signs of leaks or overtopping, and corrective measures will be taken where necessary.
5.9 OTHER WASTE PRODUCTS
Objective: To ensure that disposal of non-toxic wastes does not create visual pollution or environmental damage.
Management: Non-toxic solid wastes will be disposed of in on-site land fills, which will be operated in accordance with relevant local health authority requirements. Domestic sewage and sullage will be treated by a state-of-the-art packaged treatment system similar to that in use at BHP's recently-established Yandi project.
Monitoring: Landfills will be inspected regularly to ensure that the waste is properly buried and is not being exposed by wind, water or animals. The operation of the packaged sewage treatment system will be constantly monitored.
5.10 FIRE
Objective: To minimise the impact of the project on the frequency and severity of fires in the project area. - 45 -
Management:. BHP will maintain firefighting equipment at the mine site in case of accidental fires started by, or threatening, the project. The induction briefing given to all site personnel will include the prevention of accidental fires.
Monitoring: Fires in the area will generally be detected visually. No action will be taken unless the fire was caused by, or threatens, any aspect of the project.
- 5.11 REHABILITATION
5.11.1 Aim of Rehabilitation
BHP has developed rehabilitation procedures through its experience in the Pilbara region and will apply this experience to rehabilitation at Yarrie. The overall object of the rehabilitation programme will be to ensure that, at the end of the project, disturbed surfaces (with the exception of the mine pit) are returned to a stable condition with a flora and fauna that approach the natural condition of the site.
5.11.2 Post-Construction Rehabilitation
During the construction phase, the topsoil and vegetation on most areas to be cleared will be stripped and stored for later use in rehabilitation. At the end of construction, all areas no - - longer required (such as borrow pits, temporary access roads and hardstand areas) will be contoured (where necessary), topsoiled (where soil is available) and ripped. Where necessary, areas will be seeded with a mixture of local species. Some borrow pits will be retained for ongoing use in road maintenance.
5.11.3 Rehabilitation of Overburden
Procedures developed, by BHP over many years will be employed in the rehabilitation of the overburden storage site. At the completion of mining, a bulldozer will be used to reduce slopes to an overall angle approximating 200. The slopes will then be "moonscaped" as a harvesting technique for seed and water. The slopes will then be seeded using a mixture of local species. This technique has been used successfully for a number of years by BHP at Newman and is currently being employed on a large scale at the decommissioned operations at Mount Goldsworthy. - 46 -
5.11.4 Decommissioning
Following the completion of the Yarrie project, the village, workshops and other buildings, most local roads and other structures will be removed. Concrete slabs will be broken up and buried. The rehabilitation of overburden will be completed. Remaining borrow pits will be rehabilitated. All unwanted bare or compacted areas will be contoured (where necessary), ripped and seeded. 01. 5.11.5 Monitoring of Rehabilitation
Monitoring of rehabilitated areas will be undertaken to gauge the success of the rehabilitation. This monitoring will continue until the rehabilitated vegetation is seen to be progressing towards a condition similar to that which existed before mining. - 47 -
6.0 SOCIAL IMPACTS AND MANAGEMENT
6.1 INTRODUCTION
BHP Iron Ore and its joint venture partners have demonstrated their long-term interest in the development of the Pilbara through their operations at Newman, Nelson Point, Yandi and other satellite orebodies, and through the acquisition and upgrading of the Goldsworthy project.
Since 1990, BHP Iron Ore has committed over $500 million to these projects. The benefits of this investment to the wider community are apparent through the work and skills transfer flowing to Australian businesses; for example, the $80 million Yandi project had 81% local content and the $200 million Nelson Point project has 91% local content. Where possible, contracts have been let to Pilbara suppliers who are currently enjoying substantial benefits from these projects. The construction phase of a mining operation provides substantial work for Perth-based businesses which would otherwise be suffering the full effects of the current economic downturn.
It is proposed that the construction contracts for Yarrie will provide similar levels of benefit for local businesses, based both in the Pilbara and in other Australian centres. To maintain this level of investment, it is vital that BHP Iron Ore matches the competition it faces in the world iron ore market. International steel mills are bearing severe impacts on their profitability as a result of falls in their economies and, in turn, they are forced to call for raw material supplies at the lowest possible cost.
These international pressures mean that projects such as Yarrie cannot bear the burdens of regional development planning and historically high workforce costs. The social contribution from the Yarrie project is identified through its support for other BHP Iron Ore operations and through the direct and indirect employment it provides.
Preference will, be given to local contractors who can demonstrate their capacity and competitiveness. However, it is impractical to restrict supplier consideration to only those based in the Pilbara. -48 -
6.2 VISUAL IMPACTS
6.2.1 Visibility
The mine pit, overburden and railway line will be visible from the ground at short to medium range. The visibility from elevated vantage points such as hills and plateaux will be greater, but is still expected to be limited to a range of a few kilometres. The project will be clearly visible from the air.
6.2.2 Impact on Scenic Values
The project area is not accessible to the general public and is therefore not visited for tourism or sightseeing purposes. There will therefore be no effect on scenic values in the short or medium term.
In the long term, the Y2 mine pit will remain visible at short to medium range, while the overburden will be visible from close range as a slightly more regularly-shaped part of the plateau. At longer range, its shape will blend into the outline of the plateau. All other visible signs of the project will be removed at decommissioning. Public access to the area in the long term is expected to continue to be little or none.
6.3 ABORIGINAL INTERESTS
Ethnographic Interests Owing to the importance of the general Yarrie-Shay Gap area to Aborigines, BHP has held extensive discussions with the Aboriginal elders who are the custodians of the Yarrie area. Agreement has been reached between the company and the elders regarding the protection of religious sites in the area. A number of areas have been designated "no-go" areas for the company. These are described in the consultant's report lodged with the Aboriginal Sites Department of the Western Australian Museum and, for reasons of confidentiality, are not included here. BHP has provided written undertakings to the Aboriginal elders formalising its commitment to the agreements reached. Aboriginal people have been kept informed of the project development and have specifically indicated their approval of the sites proposed for the mine pit, overburden storage, railway line, airstrip and village.
-49-
Archaeological Sites A total of 20 archaeological sites have been identified in or near the project area. Of these, three may be disturbed by the project. These are:
an artefact scatter near Eel Creek upstream of the railway alignment; an artefact scatter on the site of the railway loadout loop; and an artefact scatter on the edge of the Yarrie plateau between the pit and overburden storage site.
These three sites were considered to be of low significance by the archaeologist who conducted the site survey. BHP has applied to the Minister for Aboriginal Affairs for permission to disturb them.
An engraving site near the western end of the railway extension has been identified as significant. This site will be protected from disturbance by maintaining clearance between it and the railway line and, if necessary, by fencing during the construction phase to prevent accidental damage by vehicles.
BHP is aware of its obligations under the Aboriginal Heritage Act 1972-1980. If any Aboriginal site is discovered during the course of development or operation of the project, work in the vicinity will stop and the Registrar of Aboriginal Sites at the Western Australian Museum will be notified.
6.4 IMPACTS ON EXISTING LAND USES I 6.4.1 Pastoral Leases
The potential impacts of the Yarrie project on pastoral leases are:
loss of grazing land to the mine and railway route; and drawdown effects on station bores due to dewatering and groundwater abstraction.
BHP has held extensive discussions with the manager of the pastoral leases on which the
1 project is located. Agreement has been reached on arrangements to avoid or ameliorate all - - potential impacts of the project on the pastoral leases. - 50 -
6.5 IMPACTS ON LOCAL COMMUNITIES
6.5.1 Aboriginal Communities
Aboriginal groups do not visit the project area and local Aboriginal station owner Mr Peter Coppin has stated that no ceremonies have been carried out in the area for many years. Shay Gap has been established since 1972 and has had little or no impact on Aborigines. Mijijimia residents have purchased food and other materials from the general store at Shay Gap for many years. There is an agreement between the Aboriginal elders and the canteen and store owners at Shay Gap that the sale of alcohol is prohibited to Aborigines from Mijijimia. This arrangement has been in effect for many years and there have been no problems.
6.5.2 Existing Workforce
The Goldsworthy operation presently has a workforce of 657, based mostly at Shay Gap and Finucane Island. The Shay Gap (Nimingarra/Sunrise Hill) mining operation is due to wind down in December 1993. Periodic mining by contractor will continue in order to fulfil some existing sales contracts. These changes are necessary for the continued economic viability of the Goldsworthy operations.
Discussions are being held with union representatives and the present mining employees to find ways to minimise the dislocation associated with the changes to the existing Shay Gap operations. Employees will be asked to give their preferences on the following options:
alternative positions elsewhere in BHP Iron Ore operations (it is likely, however, that opportunities may be limited, as the current economic climate for the iron ore industry is not conducive to producing new employment opportunities); employment with the contractor engaged to mine at Yarrie; and accepting a redundancy package.
The development of Yarrie will provide continued employment for people involved in the transport and loading of ore in the Goldsworthy operations.
6.5.3 Port Hedland
Port Hedland and South Hedland are likely to experience a small influx of people relocating from Shay Gap, and may also be a base for some new employees at the Yarrie mine site. - 51 -
6.5.4 Construction Workforce
Most of the construction workforce will be accommodated at the Yarrie construction camp and will have little impact on the communities in Shay Gap and Port Hedland.
6.5.5 Housing and Social Services
The use of on-site accommodation will mean that there will be no significant impact on demand for housing or social services in towns of the northern Pilbara.
6.6 PUBLIC CONSULTATION
6.6.1 BHP Employees
BHP Iron Ore believes that its primary responsibility is to consult with its employees in the Goldsworthy operations and has given details of the project to their union representatives at meetings in August and September 1992. Personal letters have been delivered to all employees at Shay Gap, advising them that further discussions will be held to ascertain preferences regarding options outlined in the letter.
6.6.2 Local Government Authorities
Meetings were held in September 1992 with the Mayor and Town Clerk of Port Hedland and the Shire President and Shire Clerk of the Shire of East Pilbara on the proposed Yarrie project. Further, the full Councils have received copies of the Project Proposal submitted to the Department of State Development (BHP, 1992).
6.6.3 Members of Parliament
Government and Opposition members of State Parliament and the Federal Member received personal briefings on the Yarrie project in September 1992. Their concerns were incorporated into the planning process.
6.6.4 Pastoralists and Aborigines
Issues related to the project have been discussed with pastoralists and Aborigines. - 52 -
6.6.5 General Public
The planned change to a contractor-based workforce and the consequent reduction in employment in the Goldsworthy operations has received wide coverage in the media and has stimulated discussion between BHP, trade unions, employees and the general public. This public discussion will continue throughout the development of the project. -53-
7.0 COMMITMENTS
BHP Iron Ore (Goldsworthy) Pty Limited makes the following commitments to management of environmental and social impacts with respect to the Yarrie project.
7.1 CLEARING OF VEGETATION
Only the minimum area required for construction and operation of the project will be disturbed. Where practicable, topsoil to a depth of about 15cm will be stripped and stockpiled prior to any earthmoving and, once construction is completed, all disturbed areas no longer required for the operation of the facility will be contoured (where necessary), topsoiled (where available), ripped and seeded where necessary.
7.2 DEVELOPMENT POLICY
BHP will pursue a "minimum impact" development policy which will include minimum clearing and ground disturbance, minimum groundwater abstraction, minimum water discharge, careful monitoring and effective rehabilitation. Adherence to this policy will be a requirement written / into the mining contracts.
7.3 RAILWAY CREEK CROSSINGS
Care will be exercised at all stages of construction to minimise damage to drainage channels. Culverts will be utilised along the rail route to avoid interference with the natural surface drainage. Large culverts will be utilised to cross Eel Creek.
7.4 SHADOWING EFFECTS OF RAILWAY LINE
/ BHP will establish a programme to monitor and evaluate the health of vegetation downslope of ) the railway embankment. If any adverse impacts are revealed by this monitoring, BHP will take steps as necessary to mitigate those impacts.
7.5 BORROW PITS
Borrow pits for all construction materials will be selected and operated to minimise erosion and land disturbance. Where possible, pits will be located where they are not visible from the village or access roads. The BHP-Newman Guidelines and Objectives for Borrow Pit Development and Rehabilitation (Appendix D) will be applied. - 54 -
7.6 WATER SUPPLIES
I Water supplies will be preferentially obtained from bores drilled into the Yarrie plateau adjacent to the mine pit. Water will be abstracted from the Eel Creek aquifer only if supplies from the plateau are insufficient to meet project requirements.
7.7 MONITORING OF DRAWDOWNS AND WATER QUALITY
If water is abstracted from the Eel Creek aquifer, BHP will monitor the groundwater levels and water quality in the aquifer to detect excessive drawdown or water quality changes. If significant effects are observed, the health of vegetation in the creekbed will be monitored and steps taken to mitigate adverse impacts.
7.8 SURFACE WATER DISCHARGES
Water produced from dewatering will be used, as much as possible, for domestic and mine uses. The minimum possible amount will be discharged to the natural surface drainage. BHP will monitor the quality of all water discharged to the environment from pit dewatering or other sources. Water discharged to natural drainage will comply Works Approvals and Licences issued under Part V of the Environmental Protection Act 1986.
7.9 HYDROGEOLOGICAL INVESTIGATIONS
Hydrogeological investigations will continue with the aims of better defining the aquifers of the Yarrie area, identifying sources of project water supply, predicting drawdown effects and modelling the effect of salinity buildup in the mined-out Y2 pit. The results of these investigations will be used to optimise the water abstraction and dewatering programmes and the long-term management of the mined-out pit.
7.10 EROSION CONTROL
Erosion around roads and building areas will be controlled by minimisation of clearing, rehabilitation, proper drainage and bunding where necessary. Erosion at creek crossings and culverts will be minimised by the use of rock armouring and careful design. Regular inspections will be carried out to detect and repair any erosion damage which does occur. - .55 -
7.11 OVERBURDEN
- The overburden storage site will be designed to be stable and to resist erosion. At the completion of mining, the surface of the overburden will be rehabilitated.
7.12 HAZARDOUS MATERIALS STORAGE
The handling, use and disposal of hazardous materials will comply with all local and State regulations. Bulk fuel will be stored in above-ground tanks held in impermeable, bunded enclosures, in accordance with Department of Minerals and Energy (DOME) requirements. Explosives will be stored in a magazine remote from accommodation facilities, workshops, the mine site and any areas susceptible to flooding.
7.13 OILY WASTES
Used oils will be stored securely in drums or tanks and will be periodically removed by a licensed waste disposal contractor for recycling or disposal at a Shire Council-approved site.
Runoff and wastewater from areas subject to hydrocarbon contamination, such as workshops and washdown bays, will be drained to evaporation ponds where sunlight and bacteria will decompose the hydrocarbons. Water contaminated with hydrocarbons will not be released to the environment.
7.14 LANDFILLS
Landfills for the disposal of non-toxic (including domestic) wastes will be managed in accordance with relevant local health authority requirements.
7.15 FIRE PREVENTION
BHP will maintain firefighting equipment at the mine site in case of accidental fires. The induction briefing given to all site personnel will include the prevention of accidental fires. - 56 -
7.16 WEEDS
Regular inspections of the vegetation adjacent to the railway line, roads and rehabilitated areas to ensure that weed infestation is not occurring. Any infestations discovered in the area will be dealt with by appropriate physical or chemical means.
7.17 PEBBLE-MOUND MOUSE NESTS
Disturbance of areas where Pebble-mound Mouse nests are located will be avoided wherever possible. BHP will undertake detailed surveys of Pebble-mound Mouse populations in the project area as described in Section 5.0 to provide data for their proper management.
7.18 GENERAL FLORA AND FAUNA PROTECTION
Pets (dogs and cats), firearms and indiscriminate use of off-road vehicles will be prohibited in the project area.
7.19 NOISE
Blasting will be carried out at specified times during daylight hours to minimise noise impacts at the village. Occupational noise levels will be monitored and managed as required under Works Approvals and Licences issued under Part V of the Environmental Protection Act 1986.
7.20 DUST CONTROL
Normal means of dust suppression, including watering of roads, will be employed to minimise dust generation. Occupational dust levels will be monitored and managed as required under Works Approvals and Licences issued under Part V of the Environmental Protection Act 1986.
/ 7.21 EMPLOYMENT
The mining contractor will be encouraged to source the operational workforce from the Pilbara, including Karratha and Wickham as well as Port Hedland and Newman. Former BHP employees accepting redundancy from Shay Gap will, if they indicate interest, be made known to the contractor and, if suitable, the contractor will be encouraged to employ them. - 57 -
7.22 COMMUNITY LIAISON
BHP will continue to consult with Aboriginal custodians of the project area and the owners of the neighbouring pastoral leases. BHP will respect the "no-go' areas agreed to with the Aboriginal elders.
7.23 REHABILITATION
Procedures developed by BHP in the Pilbara will be applied to rehabilitation at Yarrie. The object of the rehabilitation will be to ensure that, at the end of the project, all disturbed surfaces (with the exception of the mine pits) are returned to a stable condition with a flora and fauna which approaches the natural condition of the site.
7.24 DECOMMISSIONING
Following the completion of the project, buildings and other structures will be removed. Concrete slabs will be broken up and buried. The rehabilitation of the overburden will be completed. Remaining borrow pits will be rehabilitated. All unwanted bare or compacted areas will be contoured (where necessary), ripped and seeded. Monitoring of the rehabilitated areas will be undertaken to gauge success. This monitoring will continue until the vegetation is seen to be progressing towards a condition similar to that which existed before mining.
7.25 YARRIE PIT LONG-TERM SALINITY
BHP will continue to monitor the salinity of water in the Goldsworthy pit for several years to determine the future likelihood of saline water seeping from the pit into the De Grey River aquifer. The results of this monitoring will be used to formulate management strategies for the Yarrie pit if necessary.
7.26 PROJECT MANAGEMENT
The Yarrie project will be overseen by BHP environmental officers to ensure that the environmental management programme is adhered to. The commitments made to environmental protection in this CER will be written into the contracts for construction and mining. Regular internal audits will be carried out to ensure that the environmental management programme is being fulfilled and that no unacceptable environmental impacts are occurring. - 58 -
8.0
AGC (AGC Woodward-Clyde) (1992a). Goldsworthy Pit Water Quality Study. Prepared for BHP Iron Ore (Goldsworthy) Ltd, June 1992.
AGC (1992b). Yarrie Project - Dewatering and Water Supply. Letter to D. Podmore, BHP Iron Ore (Goldsworthy) Ltd, September 1992. r ANZECC (Australian & New Zealand Environment & Conservation Council) (1992). Draft Australian Water Quality Guidelines. Monash University: Melbourne.
BHP Engineering Pty Ltd (1992). Preliminary Geotechnical Review: Yarrie Y2 Pit North Wall. Prepared for BHP Iron Ore Ltd.
BHP Iron Ore (Goldsworthy) Ltd (1992). Goldsworthy Extension Project Phase II. BHP Iron Ore (Goldsworthy) Ltd, September 1992.
BHP-Utah Minerals International (Iron Ore) (1987). Yandicoogina (Marillana) Project. Public Environmental Report. BHP-Utah Minerals International (Iron Ore): Perth.
Blakers, M., Davies, S.J.J.F. and Reilly, P.N. (1984). The Atlas of Australian Birds. Melbourne University Press, Victoria.
Bureau of Meteorology (1988). Climatic Averages Australia. AGPS: Canberra.
Fox, J.E.D. and Van Leeuwen, S.J. (1987). Vegetation of Nimingarra Ridge. West. Aust. Inst. Technol: Report to Goldsworthy Mining Ltd.
GML (Goldsworthy Mining Limited) (1986). Goldsworthy Extension Project: Notice of Intent. Goldsworthy Mining Ltd, December 1986.
Kennedy, M. (ed.) (1990). A Complete Reference to Australia's Endangered Species. Simon and Schuster, Australia.
Kinhill Engineers (1992). Marandoo Iron Ore Project: Environmental Review and Management Programme. Prepared for Hamersley Iron Pty Ltd. -59-
Natural Resource Consultants (1986). Railroad and Environment Interaction Study. Prepared for Mount Newman Mining Co. Pty Ltd.
O'Connor, R. and Quartermaine, G. (1991). Report of a Survey for Aboriginal Sites at Shay Gap, Pilbara Region. Prepared for BHP Iron Ore (Goldsworthy) Ltd on Behalf of Nomads Management Pty Ltd, July 1991.
O'Connor, R. and Quartermaine, G. (1992). Report on Survey of Aboriginal Sites: Yarrie Mine I Development Area. Prepared for BHP Iron Ore (Goldsworthy) Ltd, October 1992.
Orsini, J. (1992). State Lists of Endangered Flora and Fauna: What Do They Mean? Wanted Alive No. 3, National Threatened Species Network, WA.
a Storr, G.M. (1984). Birds of the Pilbara Region, Western Australia. Rec. West. Aust. Mus. Suppi. No. 16.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1981). Lizards of Western Australia I. Skinks. Rec. West. Aust. Mus., Perth.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1983). Lizards of Western Australia II. Dragons and Monitors. Rec. West. Aust. Mus., Perth.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1986). Snakes of Western Australia. Rec. West. Aust. Mus., Perth.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1990). Lizards of Western Australia III. Geckos and Pygopods. Rec. West. Aust. Mus., Perth.
Strahan, R. (ed.) (1983). The Australian Museum Complete Book of Australian Mammals. Angus & Robertson, Sydney.
Tyler, M.J., Smith, L.A. and Johnstone, R.E. (1984). Frogs of Western Australia. Rec. West. Aust. Mus., Perth.
* * *
P0B:pob46021M53M71iDKP.4832 M EPA GUIDElINES FOR PREPARATION OF THE CER
PROPOSAL : GOLDSWORTHY EXTENSION PROJECT PHASE 2 (753) LOCATION : YARRIE PROJECT AREA, EAST PILBARA PROPONENT : BHP IRON ORE (GOLDSWORTHY) LIMITED SUBJECT : CONSULTATIVE ENVIRONMENTAL REVIEW GUIDELINES
Overview In Western Australia all environmental reviews are about protecting the environment. The fundamental requirement is for the proponent to describe what they propose to do, to discuss the potential environmental impacts of the proposal, and then to describe how those environmental impacts are going to be managed so that the environment is protected. If the proponent can demonstrate that the environment will be protected then the proposal will be found environmentally acceptable, if the proponent cannot show that the environment would be adequately protected then the Environmental Protection Authority (EPA) would recommend against the proposal.
Throughout the process it is the aim of the EPA to advise and assist the proponent to improve or modify the proposal in such a way that the environment is protected. Nonetheless, the environmental review in Western Australia is proponent driven, and it is up to the proponent to identify the potential environmental impacts, and design and implement proposals which protect the environment.
For this proposal protecting the environment means that the natural and social values - associated with the Yarrie area are protected. Where they cannot be protected, proposals to mitigate the impacts are required.
These Guidelines identify issues that should be addressed within the Consultative Environmental Review (CER). They are not intended to be exhaustive and the proponent may consider that other issues should also be included in the document.
The CER is intended to be a brief document, its purpose should be explained, and the contents should be concise and accurate as well as being readily understood by interested members of the public. Specialist information and technical description should be included where it assists in the understanding of the proposal. It may be appropriate to include ancillary or lengthy information in technical appendices.
Key Issues The important issues for this proposal are likely to be associated with the location of the proposal being near the De Grey River system, East Pilbara.
The key issues for the project should be clearly identified and the content of succeeding sections determined by their relevance to these issues. -2-
In this case the key issues should include:
Water supply and management issues: - groundwater impacts (abstraction and dewatering); - surface water impacts (relationship to groundwater, impacts from "railway shadow"); and salinity consideration.
Rehabilitation issues: - overburden and topsoil management; and - final land use.
Flora and fauna issues: - native flora and fauna management; and - feral flora and fauna management.
Operational management issues: - size, nature, source and impact of project workforce, during construction and operations; - dust and noise control; - waste management; decommissioning; and - potential future mining scenarios.
Infrastructure issues: - product transport options and alternative routes; - workforce transport and supplies route alternatives; and - power supply and telecommunications options.
Ethnographic and archaeological issues.
Social issues: - impacts on existing communities in the broader project area (including Shay Gap and any nomadic or settled Aboriginal groups in the broader project area) and cultural impacts for the traditional Aboriginal owners of the land; - employment impacts (implications for employment and unemployment in the northern Pilbara);
-3-
- social impacts on Port Hedland and other relevant communities of the northern Pilbara, including housing and social services; and - the management of the social impacts identified, including any ongoing liaison and impact management mechanisms proposed,
plus any other key issues raised during the preparation of the report.
Public Participation and Consultation A description should be provided of the public participation and consultation activities undertaken by the proponent in preparing the CER. This section should describe the activities undertaken, the dates, the groups and individuals involved and the objectives of the activities. This section should be cross referenced with the "environmental management" section which should clearly indicate how community concerns have been addressed. Where these concerns are dealt with via other departments or procedures, outside the Environmental Protection Authority process, these can be noted and referenced here.
Monitoring Programmes The proponent should recognise that ongoing monitoring will be required for certain aspects of the proposal, especially groundwater impacts and rehabilitation, and commit to putting a programme in place to manage these issues.
Detailed List of Environmental Commitments The commitments being made by the proponent to protect the environment should be clearly defined and separately listed. Where an environmental problem has the potential to occur, there should be a commitment to rectif' it. They should be numbered and take the form of-
0 who will do the work; what the work is; when the work will be carried out; and to whose satisfaction the work will be carried out.
- All actionable and auditable commitments made in the body of the document should be numbered and summarised in this list.
POB:sor/06021-053-071/DK135-4800
APPENDIX B
VEGETATION AND FLORA OF THE YARRIE PROJECT AREA APPENDIX B
VEGETATION AND FLORA OF THE YARRIE PROJECT AREA
1.0 INTRODUCTION
This report summarises the results of vegetation and flora surveys of the project area undertaken on 12 to 13 August 1992 and 1 to 5 October 1992. A full report of the August 1992 survey is contained in BHP (1992). During the October survey, the dominant and characteristic plants were identified in a 200m-wide railway extension route corridor, parts of the proposed transmission line route (the route could not be fully examined due to lack of aerial photographs for most of it), the mine pit area, the northeast corner of Callawa Ridge and proposed sites for the airstrip, village, office, workshop, crusher and overburden dump were recorded.
Climatic conditions during and preceding the surveys were dry and the vegetation appeared to be suffering stress as a result. Few species were in flower, and most of the spinifex was brown I and rigid and appeared to be suffering from drought. Also, there was considerable trampling of grasses and browsing of vegetation by donkeys and cattle, especially in areas of denser shrubs. The mining area had not suffered from either cattle or donkeys but had been disturbed by exploration activities.
Attempts were made during the October survey to collect voucher herbarium specimens of all flowering plant species in the survey area and in nearby significant habitats. In some cases, where no flowering specimens were found, sterile specimens were collected.
2.0 VEGETATION
All of the various facets of the project area are in the extreme northern part of the Fortescue Botanical District, with the possible exception of a part of the proposed transmission line route which is either in or very close to the Canning Botanical District to the north (Beard, 1975). Specifically, the project area is in the George Range vegetation system or physiographic unit.
The characteristic vegetation of this unit is snappy gum (Eucalyptus leucophloia) and bloodwood (E. terminalis) tree steppe on higher, rocky areas and shrub steppe on slopes, plains and broad valleys. The trees and shrubs are generally sparse, although there may be thickets of tall shrubs in drainage lines and of low shrubs elsewhere. Major drainage lines and watercourses have belts and groves of eucalypt woodland. Examples of the vegetation of the project area are shown on Plate 1. 2.1 THE RAILWAY EXTENSION ROUTE
The railway extension route corridor, because it covers the greatest area, has the greatest diversity of vegetation and number of species recorded of any facet of the project area.
Hummock grasslands, shrub steppe and tree steppe, mainly of the soft spinifex Triodia pungens, are the principal vegetation types along the railway extension route. Some of the more frequent shrub and small tree species in these steppes are Acacia ancistrocarpa, A. inaequilatera, A. aft holosericea, A. tumida, Hakea macrocarpa, H. suberea and Grevillea wickhamii. Local patches of low wattles including Acacia translucens, A. hilliana and A. adoxa occur amongst the spinifex. Infrequent Eucalyptus terminalis and E. aft grandifolia are the principal tree steppe trees.
Part of the central railway extension route traverses calcrete and rocky quartzite soils. Here Triodia wiseana and other species of spinifex are more common than Triodia pungens and the shrub Acacia bivenosa is a prominent associate. Several clumps of the somewhat salt-tolerant Acacia victoriae may indicate areas of saline soils. In recently-burnt sections of the shrub and hummock grass steppes, Clianthus formosus, Indigofera monophylla, Cassia notabilis and species of Euphorbia are prominent, at least locally in lower-lying sites, amongst seedling regeneration of Acacia species.
Eucalyptus coolabah is present on alluvial levees of some larger creeks, where Triodia longiceps tends to replace Triodia pungens as the main spinifex species. A few creek and river banks and channels have medium-sized to tall trees Eucalyptus camaldulensis, Melaleuca leucodendra and, less commonly, M. glomerata and other Melaleuca species. Cassia venusta, Ipomoea muelleri, Mukia maderaspatana, Trichodesma zeylanicum, Acacia trachycarpa, A. pyrifolia, A. ampliceps, species of Indigofera and Corcorus, and thickets of tall shrubs or short trees of Acacia tumida and A. aft holosericea are common in many drainage lines.
There are two types of wetland, each of which is represented by only one example in the corridor. One is a spring and permanent stream with a prominent low forest of Acacia ampliceps and shrub understorey of Adriane ? tomentosum in the western part of the route, near the overburden dumps associated with the Shay Gap mine pit. The vegetation of the site is far from pristine as a result of intensive use by cattle, feral donkeys and horses. The ground of the site would formerly have carried a dense grass cover of Eriachne species and the forest would have been more diverse; today only the longer-lived trees are present.
IM
The other wetland is a shallow, seasonal pool in the eastern part of the route which would, when wet, have the Nardoo fern (Marsilea sp.) and several species of ephemeral grasses. This pooi was dry at the time of the 1992 surveys.
2.2 THE MINING AREA
The vegetation of the Yarrie plateau is bloodwood (Eucalyptus terminalis) tree steppe and a shrub steppe dominated by Grevillea wickhamii, Acacia inaequilatera, other species of Acacia and, to a lesser extent, Hakea suberea and the mallee Eucalyptus odontocarpa. The plateau that includes the mining area is the only place in the survey area where this mallee was found.
Many of the drainage lines on the plateau and on the slopes below have thickets of Acacia tumida and smaller shrubs of other species and genera. Eucalypts, particularly snappy gum (E. leucophloia), are more common in the drainage lines and on the steep slopes than on the relatively flat surface of the plateau.
Some of the most prominent gullies and gorges on the slopes of the plateau are unusual in having trees of Terminalia canescens along with Atalaya hemiglauca, Ficus platypoda, Carissa lanceolata, eucalypts and a variety of shrubs. The closest prominent gully to the mining area having this type of vegetation lies west of and near the access road to the plateau. This gully is just outside the vegetation survey area and should not be any more affected by the mining project than it already has been by exploration. The only place within the survey area where this type of vegetation was found was in a valley on the slopes of Callawa Ridge.
2.3 CALLAWA RIDGE
The top of Cailawa is sparsely covered with spinifex, probably Triodia wiseana, with scattered shrubs of Grevillia wickhamii and, especially at the tops of slopes and in drainage lines, Acacia tumida. A shallow valley on the northern face of the ridge is filled with A. tumida. The next, more major valley to the west has a woodland dominated by Terminalia canescens, a spreading tree to 6m or taller. There are also whitewood (Malaya hemiglauca) and figs (Ficus platypoda) in the woodland and a few shrubs, such as Acacia pruinocarpa, which were not found elsewhere in the survey area.
The upper part of this valley, where there were two small pools in small gorges, was one of only two places in the survey area where surface water was found during the October 1992 survey.
2.4 THE AIRSTRIP
The airstrip site supports mostly spinifex grass steppe, with a belt of shrub and tree steppe of bloodwood, Acacia bivenosa, Acacia aff holosericea, Acacia inaequilatera, Grevillea wickhamii and Hakea ? chordophylla separating the spinifex-covered, gravelly caicrete rise in the eastern part of the site from the spinifex-covered red plains in the western part.
2.4 THE VILLAGE
The proposed village site surveyed in October 1992 is about 1km south of Lakes Bore, on a gentle slope immediately east of a high, narrow ridge. The vegetation of the site is basically a sparse shrub steppe comprising two species of spinifex and a species of Acacia more commonly found on the red sand ridges of the Great Sandy Desert. There are also a few shrubs of Acacia inaequilatera and Grevillea pyramidalis.
Since the October 1992 survey, the site for the camp has been changed to an area about 2.5km north-west of the mine pit. This site was not specifically surveyed in October 1992 but aerial photograph interpretation suggests that the vegetation of the site is shrub steppe with Acacia thickets and eucalypts in drainage lines. The vegetation appears to be similar to that of the office/workshop site and the eastern end of the railway extension route.
2.6 THE OFFICE AND WORKSHOP AREA
The site surveyed for the office and workshop is located at the bottom of a slope south of the Yarrie plateau. The vegetation of the site is principally a sparse layer of Triodia pungens on a rocky, pebbly substrate which is largely bare. The few shrubs are mainly Acacia pyrifolia, Acacia inaequilatera and other widespread, common species of Acacia.
Since the October 1992 survey, a possible alternative office/workshop site has been identified on the plateau north of the proposed mine pit. Aerial photograph interpretation suggests that the vegetation of this site is predominantly tree and shrub steppe, similar to that of the mine pit area.
2.7 THE CRUSHER
The crusher site vegetation is mainly a shrub steppe of spinifex and species of Acacia, probably mainly Acacia tumida, almost all of which is recovering after a recent fire. There is a small thicket of Ficus platypoda and Carissa lanceolata on the edge of the plateau above the crusher site.
2.8 THE OVERBURDEN DUMP
Like the crusher site, and bordering it, the overburden site has recently been burnt. The regenerating vegetation is a sparse tree and shrub steppe. There are greater densities of trees and shrubs, mainly of Eucalyptus and Acacia species, in drainage lines, particularly on the steeper slopes.
2.9 THE POWER TRANSMISSION LINE ROUTE
Most of the power transmission line route traverses low hills, broad valleys and plains where the vegetation is spinifex grass steppe and sparse shrub and tree steppes. Shrub and tree components are densest and most diverse where the route crosses drainage lines and creeks and runs near and parallel to them. There are fewer trees and shrubs along the transmission line route than there are in the railway extension corridor.
3.0 FLORA
More than 200 herbarium collections were made during the October 1992 survey and it is estimated that more than 150 species are represented in those collections. Additional species were recorded during the August survey, and undoubtedly the number of species recorded in the project area would be significantly increased by surveys carried out during better flowering seasons and at other times of the year. All of the species recorded to date are listed in Table 1.
The potential number of vascular plant species occurring in the project area and nearby is estimated to be in the order of 250 to 300. This is a large number compared to many parts of the Pilbara but well below the 462 species of flowering plants recorded in the Marandoo project area (Kinhill, 1992). Most of the species recorded in the survey area have wide distributions both within the project area and throughout much of the Fortescue Botanical district (Pilbara Region). Many also extend well beyond the Pilbara into Central Australia. However, several species recorded during the August and October surveys were recorded at only one or two sites in the project area and so have local significance. Some of these species are also restricted, rare or otherwise significant in the broader Pilbara region.
Species which were found at only one or two locations in the survey area include Terminalia canescens, Eucalyptus odontocarpa, Acacia sp. (village site), A. pruinocarpa, Melaleuca glomerata, Crotolaria cunninghamii, several species of Ptilotus and an as-yet unidentified pea, probably a species of Psoralea.
4.0 CONSERVATION SIGNIFICANCE
In a local sense, species recorded at only one or two locations and the vegetation types and habitats in which they were found have local conservation significance. These species are listed in the previous paragraph and in Table 1.
Species recorded in the survey area which are suspected of being rare or restricted, especially those species listed by the Department of Conservation and Land Management (CALM) as Declared Rare Flora (DRF) or Priority Flora species, and the vegetation types and habitats in which they are found, have conservation significance in a broader, regional context. The species recorded in the project area have been checked against a September 1992 working update of CALM's most recent (November 1991) master list of DRF and Priority species of Western Australia. None of the species recorded in the project area are listed as DRF or Priority Species.
5.0
The assistance of Peter Smith (Environmental Officer, BHP Iron Ore (Goldsworthy) Pty Ltd) and Greg Harold (Moloch Fauna Consultants) with the October 1992 field survey is appreciated. The help given by Malcolm Trudgen and Bruce Maslin with plant specimen identification is also appreciated. 6.0
Beard, J.S. (1975). Vegetation Survey of Western Australia. Explanatory Notes to Sheet 2, 1:1,000,000 Series: Pilbara. UWA Press, Nedlands.
BHP Iron Ore (Goldsworthy) Pty Limited (1992). Goldsworthy Extension Project Phase II. BHP, Perth.
Kinhill Engineers (1992). Marandoo Iron Ore Project: Environmental Review and Management Programme. Prepared for Hamersley Iron Pty Ltd. TABLE 1 YARRIE PROJECT AREA SYSTEMATIC LIST OF SPECIES - 1992 (interim)
FAMILY SURVEYS Species August October MARSILEACEAE Marsilea ? drummondii - - POACEAE Cymbopogon procerus (R. Br) Domin X X Cymbopogon sp. - X Eragrostis sp. - X Eriachne mucronata R. Br. X X Plactrachne melvillei C.E. Hubb - ? Plectrachne schinzii Henrad - ? Themeda australis (R.Br.) stapf. - X Triodia brizoides N. Burb X ? Triodia longiceps J. Black X X Triodia pungens R.Br. X X Triodia wiseana C. Gardner X X CYPERACEAE Cyperus aff. polystachyus Rottb. - ? Cyperus rigidellus (Benth.) J. Black X ? Fimbristylis depauperata R.Br - ? Fimbristylis oxystachya F.Muell X ? MORACEAE Ficus platypoda (Miq.) A.Cunn. ex Miq X X PROTEACEAE Grevillea pyramidalis A. Cunn. ex R.Br. X X Grevillea refracta R.Br X - Grevillea wickhamii Meisn. in DC X X Hakea chordophylla F.Muell X ? Hakea macrocarpa R.Br. X ? Hakea suberea S.Moore X X LORANTHACEAE Amyema miquelii (Lehm. ex Miq.) Tiegh. ? Amyema preissii (Miq.) Tiegh X ? CHENOPODIACEAE Dysphania rhadinostachya (F.Muell.) A.J.Scott - X Salsola kali L. - X FAMILY SURVEYS Species August October AMARANTHACEAE Aerva javanica (Burm.f.) juss ex Schultes X - Amaranthus mitchellii Benth. - ? Amaranthus viridis L. - ? Gomphrena cunninghamii (Moq.) Druce - ? Ptilotus aervoides (F.Muell.) F.Muell. - Ptilotus astrolasius F.Muell. X ? Ptilotus auriculifolius - ? Ptilotus axil1aris (F. Muell. ex Benth.) F.Muell - ? Ptilotus calostachyus F.Muell. (F.Muell.) X ? Ptilotus clementii (Farmer) Ben!. X ? Ptilotus gaudichaudii (Steudel) J. Black X ? Ptilotus gomphrenoides F.Muell. ex Benth. - ? Ptilotus obovatus (Gaud.) F.Muell X ? Ptilotus polystachyus (Gaud.) F.Muell X ? NYCTAGINACEAE Boerhavia cocci flea Miller - ? Boerhavia schomburgkiana Oliver X X GYROSTEMONACEAE Codonocarpus cotinifolius (Desf.) F.Muell - X AIZOACEAE Trianthema pilosa F. muell - MOLLUGINACEAE Mollugo molluginis (F.Muell.) Druce - X PORTULACACEAE Calandrinia affpolyandra Benth. - ? LAURACEAE Cassytha capillaris Meissner in DC. - ? Cassytha fihiformis L. - ? CAPPARACEAE Cleome viscosa L. - X Cleome sp. - X FAMILY SURVEYS Species August October MIMOSACEAE Acacia adorn Pedley X X Acacia ancistrocarpa Maiden & Blakely X X Acacia bivenosa DC X . X Acacia 'colei' ms (=A. aff. holosericea) - X Acacia farnesiana L.(Wild.) - X Acacia hilliana Maiden in Ewart & O.B. Davies X X Acacia holosericea A.Cunn. ex G.Don. X - Acacia inaequilatera Domin X X Acacia orthocarpa F.Muell. X X Acacia pruinocarpa - X Acacia pyrifolia DC X X Acacia trachycarpa E.Pritzel X X I Acacia translucens A.Cunn. ex Hooker X X Acacia tumida F.Muell. ex Benth. X X Acacia victoriae Benth. in Mitch. X - Acacia aff. victoriae - X CAESALPINACEA Cassia sp. - X Cassia glutinosa DC. X X Cassia notabilis F.Muell. X X Cassia pruinosa F.Muell. - X Cassia venusta F.Muell. X X Petalostylis labicheoides R.Br in Sturt. X X Cajanus marmoratus (R.Br. ex Benth.) F.muell. - ? Cajanus pubescens (Ewart & Morrison) van der Macsen - ? Clianthus formosus (G.Don.) Ford & Vickery X X Crotalaria crispata F.Muell. ex Benth. - ? Crotalaria cunninghamii R.Br X X Indigofera monophylla DC - ? Indigofera rugosa Benth. - ? Isotropis atropurpurea F.Muell. ? Phyllota luehmannii F.Muell. X X Psoralea pustulata F.Muell. - X ?Psoralea sp. X X Rhynocia minima (L.) DC. X X. Templetonia hookeri (F.Muell.) Benth. - ? Tephrosia bidwillii Benth. X X Tephrosia rosea F.Muell. ex Benth. X ? Tephrosia uniovulata F.Muell. ZYGOPHYLLACEAE
Kalistroemia platyptera (Benth.) Engler X ? FAMILY SURVEYS Species August October EUPHORBIACEAE Euphorbia armstrongiana Boiss. ex DC - ? Euphorbia australis Boiss. X X Euphorbia mitchelliana Boiss. in DC - ? Euphorbia schultzii Boiss. in DC - ? Euphorbia sp. - X Flueggea virosa (Roxb. ex Wild.) Voigt subspecies melanthoides (F.Muell.) Webster - X Phyllanthus maderaspatensis L. ?
SAPINDACEAE Atalaya hemiglauca (F.Muell.) F.Muell. ex Benth X X Dodonaea coriacea (Ewart & O.B. Davies) D. McGillivray - ? TILLIACEAE Corchorus parviflorus Domin - ? Corchorus wakottii F.Muell. X X Triumfetta appendiculata F.Muell. - ? Triumfetta micranthcz F.Muell. X ? Triumfetta plumigera F. Much. X X MALVACEAE Abutilon exonemum F.Muell. X ? Abutilon fraseri (Hook.) Hook. ex Waip. - ? Hibiscus coatesii F.Muell. X ? Sida clementii Domin X ? Sida rohlenae Domin - ? - ? , Sida virgata Hook. in Mitch ELATINACEAE Bergia pedicellaris (F.Muell.) Benth. - ? COMBRETACEAE Terminalia canescens (DC.) Radik. X X MYRTACEAE Eucalyptus camaldulensis Dehuh. X X Eucalyptus coolabah Blakely & Jacobs X X Eucalyptus leucophloia Brooker X X Eucalyptus odontocarpa - X Eucalyptus affpapuana F.Muell. X - Eucalyptus terminalis F.Muell. X X Melaleuca glomerata F.Muell. X X Melaleuca lasiandra F.Muell. - ? Melaleuca leucadendra (L.)L. X X APIACEAE Trachymene oleracea (Domin) B.L.Burtt. X X FAMILY SURVEYS Species August October OLEACEAE Jasminum lineare R.Br. X X APOCYNACEAE Carl ssa I,anceolata R.Br. X X CONVOLVULACEAE Bonamia rosea (F.Muell.) H.Hallier - ? Evolvulus alsinoides (L.) L. X Ipomoea muelleri Benth. X X BORAGINACEAE Ehretia saligna R.Br. - X Heliotropium cunninghamii Benth. - ? Heliotropium ovalifolium Forsskal. - ? Trichodesma zeylanicum (Burm f.) R.Br. X X VERBENACEAE Clerodendrum floribundum R.Br. - ? Clerodendrum lanceolatum F.muell. X ? Clerodendrum tomentosum (Vent.) R.Br. - ? SCROPHULARIACEAE Stemodia grossa - X Stemodia kingii - ? SOLANACEAE Nicotiana benthamiana Domin. - ? Solanum dioicum W.V.Fitzg. X ? Solanum diversiflorum F.Muell. - ? Solanum lasiophyllum Dunal ex Poir. in Lam X X Solanum phiomoides Cunn. ex Benth. - ? RUBIACEAE Pomax umbellata (Sol. ex Gaertner) Miq. - ? ACANTHACEAE Dicladanthera forrestii - ? CUCURBITACEAE Mukia maderaspatana (L.) M.Roemer X X GOODENIACEAE Dampiera candicans F.Muell. X - Goodenia microptera F.Muell. X X Goodenia scaeuolina F.Muell. X X Goodenia sp. (in press) - ? Scaevola brownia Carolin & Dyer FAMILY SURVEYS Species August October ASTERACEAE Chyrsogonum trichodesmoides (F.Muell.) F.Muell. - ? Pluchea tetranthera F.Muell. - X Pterocaulon glandulosum F.Muell. X X Pterocaulon sphaeranthoides (DC.) F.Muell. - X Streptoglossa decurrens (DC.) C.R. Dunlop X ? Widelia sp. - X
Botanical names after J.W.Green (1985), Census of the Vascular Plants of Western Australia (Second Edition), WA. Herbarium, Department of Agriculture, Perth CAPTIONS - PLATE 1
Shrub and tree steppe, with Acacia inaequilatera and low thickets of Acacia hilliana and A. translucens at north-western end of railway extension route. Patchily-burnt steppe in north-western part of railway extension route. Spinifex hummock grass steppe in south-eastern part of railway extension route, with thickets of Acacic tumida and A. aff holosericea in drainage lines. Shrub and tree steppe, denser and with thickets in drainage lines, in railway extension loop area. Callawa ridge in background. Looking across overburden dump site to crusher site (on cliff) and mining area (on plateau). Spinifex and shrub steppe regenerating after fire. Regenerating bloodwoods, cabbage gums (E. affgrandifolia) and thickets of shrubs in drainage lines. Acacia ampliceps low forest and dam which catches water from spring in forest near Shay Gap overburden dump, near north-western end of railway extension route. Dry, ephemeral grasses and Marsilea ? drummondii in ephemeral pond on railway extension route. White-flowered pea, Acacia ampliceps and A. aff holosericea thickets on bank.
'I 5 .1' kl APPENDIX C
FAUNA SURVEY OF THE YARRIE PROJECT AREA APPENDiX C
FAUNA SURVEY OF TILE YARRIE PROJECT AREA
1.0
A four-day field assessment was carried out at Yarrie between 2 and 5 October 1992. All major habitats, including those in the proposed mining area and its associated infrastructure, were examined. All fauna observed were recorded and are listed in Table 1. This table also includes species which would reasonably be expected to occur in the area and could be recorded given sufficient survey time and favourable seasons.
2.0 HABITATS
The habitats of the study area are mostly typical of the Pilbara in general, though lacking in, the shrublands that are found further to the south and west. For the purposes of this studl habitats have been divided into four broad categories:
Creeks and claypans - all those which have a clearly defined belt of fringing vegetation, usually consisting mostly of eucalypts.
Hills and stony rises - hills, cliff faces, scree slopes and low-lying rocky areas. Vegetation mostly consists of spinifex (Triodia sp.) with sparse shrubs and a few taller trees, mostly eucalypts. Large areas have recently been burnt.
Spinifex plains - all valley floor habitats on sandy, loamy and stony substrates. Vegetation is mainly Triodia with occasional areas of low shrubs and some taller trees, usually eucalypts. Large areas have recently been burnt.
Great Sandy Desert - a small section of this area occurs on or just north of the proposed power line route north of the Shay Gap townsite. Vegetation is mainly low shrubs over Triodia on loamy to sandy soils.
Creeks and Claypans The vegetation of these areas, as described in Appendix B, is multi-strata! (usually three or four strata are present) with the upper canopy dominated by trees. This structure provides opportunities for vertical separation of habitat use by some species. Thus, for example, parrots and tree martins may primarily use the hollow limbs and trunks of the trees while honeyeaters C-2 may use the shrubby, floristically-diverse middle strata and finches may use the seed- producing grasses and small shrubs of the lowest stratum.
This structural and floristic richness, when compared to the hills and plains, makes the creekside areas richer in faunal habitat and hence of greater significance. Most of the fauna expected in this habitat are common and widespread.
Hills and Stony Rises The hills and stony rises provide two habitat types not found elsewhere in the project area. These are shaded gullies and rocky shelters. Most of the regional habitat is very dry and hot for most of the year. Respite from these conditions becomes a priority for most fauna.
Deep gullies, where they occur in hills or on the sides of plateaux, provide shade for more of the day than do more exposed areas. They also trap moisture and, after rain or dew, retain it for longer than exposed areas. It is for these reasons that floral species richness is often greater, and some reptiles more abundant, in gullies.
Caves, cliff faces and scree slopes likewise provide shelter in holes and crevices or amongst large boulders. These habitats have significance both for opportunistic fauna and for species that are specifically adapted to these habitats. Fauna in these habitats may be restricted in distribution and uncommon. This type of habitat is common in the project area and in surrounding areas.
Spinifex Plains These broad, structurally-homogeneous habitats (only one or two strata) support a non-specialised fauna. Most of the inhabitants are cryptic (often living in burrows or under spinifex clumps) and/or nocturnal in habit. Most .of the fauna of the spinifex plains are common and widespread.
Great Sandy Desert This habitat type consists of scattered low shrubs over spinifex on sandy or loamy soils. In terms of faunal habitat it is similar to the spinifex plains in that it is structurally homogeneous (mostly only one stratum) and covers a wide area. Again, the majority of the fauna are burrowing, cryptic and/or nocturnal. They are also mostly very common and widespread. C-3
3.0 VERTEBRATE FAUNA
The faunal assemblages observed during the 1992 survey included 35 birds, 5 mammals, 1 amphibian and 7 reptiles. All of the birds were common, even the Wood Sandpiper (Tringa glareola) which was observed near a spring at the western end of the railway route. This bird is a northern hemisphere migrant that visits the greater part of the Pilbara although it is of infrequent occurrence (Storr, 1984). It is usually recorded on river pools, sewage ponds, freshwater lagoons and bore overflows. The absence of shrublands of any magnitude has reduced the number of expected species, especially of small insectivorous birds. The close proximity of the Great Sandy Desert necessitates the inclusion of a number of species, mainly reptiles, not included in the typical Pilbara fauna.
Amongst the mammals, the Ghost Bat and Pebble-mound Mouse were notable observations. These are discussed below. The amphibian and reptile species observed are all common and widespread.
4.0 RARE FAUNA
Listed in Table 1 are a number of species protected under the Wildlife Conservation Act 1950. These gazetted species are listed under two schedules; Schedule 1 ('Threatened List') species are described as 'fauna that are likely to become extinct or are rare', with Schedule 2 ('Reserve List') species being described as 'in need of special protection'. Although species on the 'Reserve' list are not afforded any special protection, attention should be directed to these species to ensure that they do not join the 'Threatened' list (Schedule 1) in the near future (Orsini, 1992).
Schedule 1 Evidence of two Schedule 1 species, the Pebble-mound Mouse and the Bilby, was found in the project area. o Pebble-mound Mouse (Pseudomys chapmani). This species is restricted to the Pilbara and builds distinctive mound nests of small pebbles. The distribution of the Pebble- mound mouse is uncertain but it is locally abundant in the Hamersley Range (Karijini) National Park. Dunlop and Pound (1981) record the Pebble-mound Mouse as inhabiting rocky, hummock grassland areas with little or no soil but with a plentiful supply of pebbles, derived from iron formation ridges and dolomite outcrops. The C-4
Pebble-mound Mouse was described in Fisheries and Wildlife (1983) as "a species with very restricted geographical range" and "a species with drastically reduced range since European settlement".
Many mound nests of this species were observed to the east of the proposed mining area. It appeared that approximately 50% of these mounds were active, with obvious well-maintained burrow entrances.
Bilby (Macrotis lagotis). Sometimes known as the Rabbit-eared Bandicoot or Dalgyte, this species constructs burrows in deep soils. In the Pilbara it is therefore restricted to alluvial landforms or, in rocky areas; to minor waterways with loamy soils; Bilby burrows have been found as far west as the Paraburdoo area (J.E. Kinnear, in Ninox Wildlife Consulting, 1985), and an extant population occurs on Woodstock Station. Other populations occur in the desert to the east, but abundance and distribution remain largely unknown. The Bilby is nomadic and "home ranges are temporary in location and may suddenly be shifted in response to changing availability of food" (K.A. Johnson, in Strahan, 1983). It was described in Fisheries and Wildlife (1983) as " a species with drastically reduced range since European settlement". Since European settlement, the Bilby has suffered a 50-90% diminution of its former range (Kennedy, 1990). Several Bilbies have been sighted around Shay Gap by BHP personnel in recent years. In 1991, one of two road kill specimens was sent to the Western Australian Museum for positive identification.
A disused burrow system possibly belonging to this species was recorded in friable, loamy soil adjacent to a creekbed in the south-eastern section of the proposed rail route.
Other Schedule 1 species not recorded, but which might be present in the project area, are the Mulgara, Lesser Stick-nest Rat and Grey Falcon.
Mulgara (Dasycercus cristicauda). The Mulgara inhabits and sandy regions of the Great Sandy Desert, southern Northern Territory and northern South Australia. It lives in burrows in interdunal troughs and appears to be largely solitary. It was last collected in Western Australia in 1959. If it occurred in the project area it would only be in the very small section of Great Sandy Desert habitat at the northern extremity of the proposed power line route. C-5
Lesser Stick-nest Rat (Leporillus apicalis). This rat was described in Fisheries and Wildlife (1983) as "probably extinct". It formerly ranged over much of central Australia as evidenced by the remains of its bitumen-like nests, which can be found in small caves and breakaways. There are, however, several unconfirmed reports of contemporary nests (Gratte, 1972; Ninox Wildlife Consulting, 1985). Although the possibility of finding this species within the project area is low, it cannot be discounted entirely.
Grey Falcon (Falco hypoleucos). Considered by Fisheries and Wildlife (1983) to be a "species with widespread distribution but which is very rare', and "in need of special protection", this species has a wide distribution throughout inland Australia and is considered to be one of Australia's rarest raptors. The potential threats to its survival are overgrazing, degradation of riparian habitats and pesticides (Kennedy, 1990). It could occur at Yarrie but would be unaffected by the project.
Schedule 2 One Schedule 2 species, the Pilbara Rock Python, was observed during the 1992 field survey.
Pilbara Rock Python (Morelia olivaceus barroni). This is the endemic Pilbara race of the far more widespread, tropical Olive Python. Its preferred habitat is near pools in creeks and rivers. It was described in Fisheries and Wildlife (1983) as a 'species with very restricted geographical range". A single specimen was observed in a rock pooi at the head of a gully on the Callawa plateau.
Other Schedule 2 species not observed but which may be present are the Peregrine Falcon and Woma Python.
Peregrine Falcon (Falco peregrinus). Described by Fisheries and Wildlife (1983) as "in need -of special protection", this species is widely distributed in Australia. Its status is considered to be "generally uncommon, probably declining in settled regions; still well established in remote areas" (Pizzey, 1980). It is not dependant on any habitat which occurs within the project area. This species has a worldwide distribution, with birth defects and egg-shell thinning due to pesticide ingestion being thought to be the main causes of its decline. Other threats to its survival include illegal trade and shooting (Kennedy, 1990). C-6
Woma Python (Aspidites ramsayi). The Woma occurs throughout the desert areas of central Australia and is present in all mainland states except Victoria. It is found mainly in sandhils, where it burrows under spinifex clumps or occupies hollow logs or animal burrows during the day. It is most likely to occur in the small section of Great Sandy Desert at the northern extremity of the power line route. It would not be endangered by the project.
5.0 OThER FAUNA OF NOTE
Other significant fauna, not formally gazetted as Schedule 1 or 2 species, which were observed or may occur in the project area are the Ghost Bat, Rothschild's Rock-wallaby, Orange Horseshoe-bat and Long-tailed Dunnart.
Ghost Bat (Macroderma gigas). A single, mummified specimen of this species was found on a barbed-wire fence near the proposed rail ioop. This species is protected under the International Union for the Conservation of Nature (IUCN) and its inclusion in the WA 'Reserve' (Schedule 2) list is presently awaiting ministerial approval. This species would most probably be using the many roosting caves located in the cliff faces throughout the area. Some local impact is possible due to disturbance on the margins of the Yarrie plateau by placement of overburden. The area of disturbance will, however, be small.
Rothschild's Rock-wallaby (Pet rogak rothschildi). Although this species is not currently gazetted, its rarity over large areas of apparently suitable habitat in the Pilbara and western Gascoyne, to which it is restricted, requires its inclusion in this report. Its preferred habitats are rocky scree slopes, gorges and rock formations with small caves and crevices which provide shelter from the elements and predators. When discussing a survey of this species in the Paraburdoo area, Dr J.E. Kinnear (CALM, pers. comm.) indicated "The surveys have revealed that, whenever populations of P. rothschildi are discovered on the mainland, the population densities are invariably low. Moreover, the species is frequently abs ent from sites which would appear to be prime habitat. These findings are not encouraging and imply that the species is endangered." Suitable habitat for P. rothschildi is present, but not abundant, in the project area and little will be disturbed by the project. No indications of P. rothschildi were found during the survey. I
C-7
Orange Horseshoe-bat (Rhinonicteris aurantius). This bat occurs in the Kimberley region, Northern Territory and around the Gulf of Carpentaria into Queensland. There is a single record from the central Pilbara. It was originally thought to roost in hollow trees but has since only been found in caves. Colonies range from a few individuals to several thousands. It is reported to favour deep, warm, humid caves. It is susceptible to disturbance and may leave an area entirely following repeated disturbance. It is unlikely to be present at Yarrie due to the apparent lack of suitably large, humid caves.
Long-tailed Dunnart (Sminthopsis longicaudata). This species is currently gazetted as "I, species of uncertain status". It formerly occurred over much of central-western Australia and, prior to 1975, was only known from three specimens from the Marble Bar area and "Central Australia". Since then it has been recorded from the Gibson Desert (Miss Gibson Hill, the Young Range), the Pilbara (Paraburdoo area) and near Mt Anderson on Depot Springs Station, east of Sandstone. The habitat data established from the records indicate that its apparent rarity is probably a result of the great difficulty in capturing this species. In view of the existence of large areas of suitable habitat (rugged scree slopes) from the Pilbara to the northern goldfields, it is probably much more common than current records suggest.
6.0 FERAL ANIMALS
During the field assessment two groups of Donkeys, each containing six animals, were observed. Due to the number of tracks and droppings recorded in the area the total local population must be substantially higher than the number observed. Other feral species that possibly occur are the Fox, Cat, House Mouse, Goat, Horse and Camel. No obvious signs of these animals were apparent during the assessment and their numbers may be low owing to the successive poor seasons experienced in the area.
7.0 REFERENCES
Blakers, M., Davies, S.J.J.F. and Reilly, P.N. (1984). The Atlas of Australian Birds. Melbourne University Press, Victoria.
Dunlop, J.N. and Pound, I.R. (1981). Observations on the Pebble-mound Mouse, Pséudomys chapmani Kitchener 1980. Rec. West. Aust. Mus. 9(1). I
Fisheries and Wildlife (1983). Second Schedule of Fauna Which is Rare or Otherwise in Need of Special Protection. Swans 13:28-30.
Gratte, S. (1972). The Stick-nest Rat, Leporillus conditor, in the Gibson Desert. West. Aust. Nat. 12 (3): 50-51.
Kennedy, M. (ed) (1990). A Complete Reference to Australia's Endangered Species. Simon and Shuster, Australia.
Ninox Wildlife Consulting (1985). An internal report to Hamersley Iron Pty Ltd. Unpublished.
Orsini, J. (1992). 'State Lists of Endangered Flora and Fauna: What Do They Mean?' Wanted Alive No.3, National Threatened Species Network, WA.
Pizzey, G. (1980). A Field Guide to the Birds of Australia. W. Collins Ltd, Sydney.
Storr, G.M. (1984). Birds of the Pilbara Region, Western Australia. Rec. West. Aust. Mus. Suppi. No.16.
Storr, G. M., Smith, L.A. and Johnstone, R.E. (1983). Lizards of Western Australia II. Dragons and Monitors. Rec. West. Aust. Mus., Perth.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1986) Snakes of Western Australia. Rec. West. Aust. Mus., Perth.
Storr, G.M., Smith, L.A. and Johnstone, R.E. (1990) Lizards of Western Australia III. Geckos and Pygopods. Rec. West. Aust. Mus., Perth.
Strahan, R. (ed) (1983) The Australian Museum Complete Book of Australian Mammals. Angus & Robertson, Sydney.
Tyler, M.J., Smith, L.A. and Johnstone, R.E. (1984) Frogs of Western Australia. Rec West Aust. Mus., Perth. I
TABLE 1
LIST OF VERTEBRATE SPECIES RECORDED OR EXPECTED TO OCCUR AT YARRIE - OCTOBER 1992
HABITATS 1 - Creeks and claypans 2 - Hills and stony rises 3 - Spinifex plains, stony and sandy soils 4 - Great Sandy Desert
KEY X - species likely to occur R - species recorded during field assessment * - Gazetted species - Schedule 1 "- Gazetted species - Schedule 2
HABITATS 1 2 3 4 BIRDS DROMAIIDAE Dromaius novaehollandiae Emu X X X X PODICIPEDIDAE Poliocephalus poliocephalus Hoary-headed Grebe X Tachybaptus novaehollandiae Australasian Grebe R ARDEIDAE Ardea pacifica Pacific Heron R A. novaehollandiae White-faced Heron X Egretta alba Great Egret X E. garzetta Little Egret X PLATALEIDAE Plegadis falcinellus Glossy This X Threskiornis aethiopica Sacred This X Platalea flavipes Yellow-billed Spoonbill X ANATIDAE Dendrocygna eytoni Plumed Whistling-Duck X Cygnus atratus Black Swan X Anas superciliosa Pacific Black Duck X A. gibberifrons Grey Teal R Malacorhynchus membranaceus Pink-eared Duck X Aythya australia Hardhead X Chenonetta jubata Maned Duck X ACCIPITRIDAE Elanus notatus Black-shouldered Kite X X X X Milvus migrans Black Kite X X X X Hamirostra melanosternon Black-breasted Kite X X X X Haliastur spenurus Whistling Kite R X X X Accipiter fasciatus Brown Goshawk X X X X A. ci rrhocephal us Collared Sparrowhawk X X X X Aquila audax Wedge-tailed Eagle X X R X Hieraaetus morphnoides Little Eagle X X X X Cirus assimilis Spotted Harrier X X X X HABITATS 1 2 3 4 FALCONIDAE Falco peregrinus Peregrine Falcon" X X X X F. longipennis Australian Hobby X X X X F. hypoleucos Grey Falcon * X X X X F. berigora Brown Falcon X R R X cenchroides Australian Kestrel X X X X TURNICIDAE Turnix velox Little Button-quail X X X RALLIDAE Gallinula ventralis Black-tailed Native-hen X Fulica atra Eurasian Coot X OTIDIDAE Ardeotis australis Australian Bustard X X X BURHINIDAE Burhinus magnirostris Bush Thick-knee X X X CHARADRIIDAE Erythrogonys cinctus Red-kneed Dotterel X Charadrius veredus Oriental Plover X C. ruficapillus Red-capped Plover X C. melanops Black-fronted Plover X RECURVIROSTRIDAE Himantopus himantopus Black-winged Stilt X Recurvirostra novaehollandiae Red-necked Avocet X SCOLOPACIDAE Tringa glareola Wood Sandpiper R T. hypoleucos Common Sandpiper X T. nebularia Greenshank X Calidris acuminata Sharp-tailed Sandpiper X C. ruficollis Red-necked Stint X C. subminuta Long-toed Stint X C. ferruginea Curlew Sandpiper X GLAREOLIDAE Glareola maldivarum Oriental Pratincole X X Stiltia isabella Australian Pratincole X X COLUMBIDAE Geopelia placida Peaceful Dove X X cumeata Diamond Dove X X Phaps chalcoptera Common Bronzewing X X Ocyphaps lophotes Crested Pigeon X X Petrophassa plumifera Spinifex Pigeon R R X CACATUIDAE Cacatua roseicapilla Galah R R X C. sanguinea Little Corella R R X HABITATS 1 2 3 4 POLYTELITIDAE Nymphicus hollandicus Cockatiel X X X PLATYCERCIDAE Melopsittacus undulatus Budgerigar X X X Barnardius zonarius Port Lincoln Ringneck X X CUCULIDAE Cuculus pallidus Pallid Cuckoo X R X Chrysoccyx basalis Horsfield's Bronze-cuckoo x X STRIGIDAE Njnox novaeseelandjae Southern Boobook Owl X N. connivens Barking Owl X TYTONIDAE Tyto alba Barn Owl X PODARGIDAE Podargus strigoides Tawny Frogmouth X X AEGOTHELIDAE Aegotheles cri status Australian Owlet-nightjar X X CAPRIMULGIDAE Caprimulgus guttatus Spotted Nightjar X X R X APODIDAE Apus pacificus Fork-tailed Swift X X X X ALCEDINIDAE Dacelo leachii Blue-winged Kookaburra R Halcyon pyrrhopygia Red-backed Kingfisher X X H. sancta Sacred Kingfisher X X MEROPIDAE Merops ornatus Rainbow Bee-eater R X R X ALAUDIDAE Nirafra javanica Singing Bushlark X X HIRUNDINIDAE Cheramoeca leucosternum White-backed Swallow X X X Hirundo neoxena Welcome Swallow X Cecropis nigricans Tree Martin X C. ariel Fairy Martin R MOTACILLIDAE
Anthus novaeseelandiae Richard's Pipit R R X HABITATS 1 2 3 4
CAMPEPHAGIDAE Coracina novaehollandiae Black-faced Cuckoo-shrike R R R X Lalage sueurii White-winged Trifler X X X MUSCICAPIDAE Melanodryas cucullata Hooded Robin X X X X Pachycephala rufiventris Rufous Whistler X Collucicincla harmonica Grey Shrike-thrush R R Oreoica gutturalia Crested Beilbird X X Rhipidura leucophrys Willie Wagtail X R X X TIMALIIDAE Pomatostomus emporalis Grey-crowned Babbler X X SYLVIIDAE Eremiornis carteri Spinifex Bird X R Cinclorhamphus mathewsi Rufous Songlark X X C. cruralis Brown Songlark X X X MALURIDAE Malurus lamberti Variegated Fairy-wren X X X M. leucopterus White-winged Fairy-wren X X X Stipiturus ruficeps Rufous-crowned Emu-wren X X Amytornis striatus Striated Grasswren X R ACANTHIZIDAE Smicrornis brevirostris Weebill X X NEOSITTIDAE Daphoenositta chrysoptera Varied Sittella X CLIMACTERIDAE Climacteris melanura Black-tailed Treecreeper X X X MELIPHAGIDAE Acanthagenys rufogularis Spiny-cheeked Honeyeater X Manorina flavigula Yellow-throated Miner R R Lichenostomus virescens Singing Honeyeater X R L. keartlandi Grey-headed Honeyeater R R R L. plumulus Grey-fronted Honeyeater X X X L. penicillatus White-plumed Honeyeater R Melithreptus gularis Black-chinned Honeyeater X X Lichmera indistincta Brown Honeyeater R R Phylidonyris albifrons White-fronted Honeater X X X Certhionyx niger Black Honeyeater X X X X C. variegatus Pied Honeyeater X X X X EPHTHIANURIDAE Ephthianura tricolor Crimson Chat X X X X E. aurifrons Orange Chat X X X X DICAEIDAE Dicaeum hirundinaceum Mistletoebird X X X X HABITATS 1 2 3 4 PARDALOTIDAE Pardalotus rubricatus Red-browed Pardalote R R P. striatus Striated Pardalote X X PLOCEIDAE Emblema picta Painted Firetail X R Neochmia ruficauda Star Finch X Poephila guttata Zebra Finch R X R X PARADISAEIDAE Chiamydera maculata Spotted Bowerbird X X GRALLINIDAE Grallina cyanoleuca Australian Magpie-lark R ARTAMIDAE Artamus leucorhynchus White-breasted Woodswallow X X X X A. personcztus Masked Woodswallow X X X X A. cinereus Black-faced Woodswallow R R R X A. minor Little Woodswallow R R CRACTICIDAE Cracticus torquatus Grey Butcherbird X X C. nigrogularis Pied Butcherbird X R R Gymnorhina tibicen Australian Magpie X X X CORVIDAE Corvus bennetti Little Crow R X X X C. orru Torresian Crow R X R X
TACHYGLOSSIDAE Tachyglossus aculeatus Short-beaked Echidna X X X X DASYURIDAE Dasyurus hallucatus Northern Quoll X Dasycercus cristicauda Mulgara* X Dasykaluta rosamondae Little Red Antechinus X Pseudantechinus macdonnellensis Fat-tailed Antechinus X X Sminthopsis longicaudata Long-tailed Dunnart X S. macroura Stripe-faced Dunnart X X X Ningaui timealeyi Pilbara Ningaui X X Planigale maculata Common Planigale X X P. ingrami Long-tailed Planigale X X THYLACOMYIDAE Macrotis lagotis Bilby* X X X MACROPODIDAE Petrogale rothschildi Rothschild's Rock-wallaby X Macropus robustus Common Wallaroo or Euro X X X M. rufus Red Kangaroo X R X HABITATS 1 2 3 4 MEGADERMATIDAE Macroderma gigas Ghost Bat X X R X EMBALLONURIDAE Saccolaimus flaviventris Yellow-bellied Sheathtail-bat X X X X Taphozous georgianus Common Sheathtail-bat X X X X Taphozous hilli Hill's Sheathtail-bat X X X X MOLOSSIDAE Chaerephon jobensis Northern Mastiff-bat X X X X VESPERTILIONIDAE Nyctophilus geoffroyi Lesser Long-eared Bat X X X X Chalinolobus gouldii Gould's Wattled Bat X X X X Eptesicus finlaysoni Western Cave Eptesicus X X X X Rhinonicteris aurantius Orange Horseshoe-bat X X X X Scotorepens greyii Little Broad-nosed Bat X X X X MURIDAE Zyzomys argurus Common Rock-rat X Pseudomys dehicatulus Delicate Mouse X P. hermannsburgensis Sandy Inland Mouse X X P. chapmani Pebble-mound Mouse* R Notomys alexis Spinifex Hopping-mouse X X Mus musculus House Mouse X X X X CANIDAE Canis Famihiaris dingo Dingo R X X X Vulpesvulpes Fox X X .X X FELIDAE F Felis catus Feral Cat X X X X EQUIDAE Equus caballus Horse X X X X Equus asinus Donkey R X R X CAMELIDAE Camelus dromedarius One-humped Camel X X X BOVIDAE Capra hircus Feral Goat X X X X AMPHIBIANS
LEPTODOCTYLIDAE Limnodynastes spenceri X X Neobatrachus centrahis X X X Uperoleia russelhi R HABITATS 1 2 3 4 HYLIDAE Cyclorana australis X X C.maini X X platycephala X X Litoria rubella X REPTILES
GEKKONIDAE Geckos Crenadactylus ocellatus horni X X Diplodactylus ciliaris aberrans X X conspicillatus X X D.elderi x x x x D.jeanae X X D. pukher X D. savagei X S. stenodactylus X X D. wellingtonae X X X D. wombeyi X X Gehyra pilbara X G. punctata X G. pururescens X variegata R X X Heteronotia bincei X X X X spelea X Nephrurus levis pilbarensis X X N. w. wheeleri X X Oedura marmorata X Rhynchoedura ornata X X PYGOPODIDAE Legless Lizards Delma borea X X X D. butleri X X D. nasuta X X D.pax X X Lialis burtonis X X X X Pygopus nigriceps nigriceps X X X AGAMIDAE Dragon Lizards Ctenophorus c. caudicinctus R C.inermis R R X C. i. isolepis R X Diporiphora winneckei X X Gemmatophor longirostris X Pogona minor mitchelli X X X Tympanocryptis cephala X X HABITATS 1 2 3 4 SCINCIDAE Skinks Carlia triacantha X X Cryptoblepharus carnabyi R C. plagiocephalus X X X Ctenotus ariadnae X C. calurus X C. duricola X X C. grandis titan X C. hanloni X VARANIDAE Monitors Varanus acanthurus X X X V. brevicauda X X X V. caudolineatus X X X V. eremius X X V. giganteus X X X X B. gilleni X X X V.gouldii X R X V. panoptes rubidus X V. pilbarensis X V.t.tristis X X X TYPHOLOPIDAE Blind Snakes Ramphotyphiops diversus ammodytes X X X R. endoterus X R.grypus X X X R. hamatus X X X waitii X X X BOIDAE Pythons Aspidites melanocephalus X X X A. ramsayi X Morelia olivaceus barroni' R Liasis perthensis X X X L. stimsoni stimsoni X X X X ELAPIDAE Elapid Snakes Acanthophis pyrrhus X X X X Demansia psammophis cupreiceps X X X X D.rufescens X X X X Denisonia fasciata X X X X Furina ornata X X X X Pseudechis australis X X X X Pseudonaja modesta X X X X P. nuchalis X X X X Rhinoplocephalus monachus X X X X Simoselaps anomalus X approximans X X X S. bertholdi X X Vermicella multifasciata snelli w FAXWupi DJI4iI
BlIP-NEWMAN GUIDEUNES AND OBJECTWES FOR BORROW PIT DEVELOPMENT AND REHABILITATION GUIDELINES AND OBJIECTWES FOR BORROW PIT DEVELOPMENT AND REHABILITATION
K.J. Walker Rehabilitation Officer BHP Iron Ore Pty Limited TABLE OF CONTENTS
Page No.
1.0 ABSTCT 1 0 2.0 INTRODUCTION 1
3.0 SECTION A - PROPOSED PITS 2 3.1 PLANNING 2 3.2 LOCATION AND ACCESS 2 3.3 WATERCOURSES 3 3.4 SIZE OF BORROW PITS 3 3.5 CLEARING AND STOCKPILING OF OVERBURDEN AND TOPSOIL 4 3.6 REMOVAL OF BORROW PIT MATERIAL 5
4.0 ENVIRONMENTAL IMPACTS OF BORROW PITS 5
5.0 FUTURE USES OF BORROW PITS 6
6.0 SECTION B - REHABILITATION 6 6.1 INDUSTRIAL RUBBISH 6 6.2 LANDSCAPING 6 6.3 SPREADING TOPSOIL 7 6.4 SPREADING OVERBURDEN 8 6.5 RIPPING 8 6.6 SEEDING 8
7.0 SECTION C - REHABILITATION - OLD BORROW PITS 8 7.1 LANDSCAPING 9 7.2 TOPSOIL AND OVERBURDEN 9 7.3 RIPPING 9 7.4 OLD ROADS AND DISTURBANCES 9
8.0 SUPPLEMENTARY TREATMENTS 10
9.0 SUMMARY 10
10.0 BORROW PIT TECHNICAL DATA 10
11.0 PROPOSED BORROW PITS - PROGRESSIVE CHECKLIST 11
12.0 CONTRACTORS BORROW PIT DEVELOPMENT AND REHABILITATION CHECKLIST 12
GUIDELINES AND OBJECTWES FOR BORROW PIT DEVELOPMENT AND REHABILITATION
1.0 ABSTRACT
The following is an outline of the principles and objectives for management and rehabilitation of borrow pits. Borrow pit is a term describing an area where gravel, sand and general material for road making, building and fill is obtained. It can also describe any quarry or open cut mining operations, operations associated with road building, mining operations, railroad operations and industrial sites.
These guidelines are intended for soil, gravel and sand extraction with rehabilitation specifically using indigenous (local) species as treatment of these areas being highlighted.
Rehabilitation is the term used to describe the physical landscaping and improvement of a disturbed area to promote and encourage the return of vegetation and prevent erosion to that area.
The principal objective of rehabilitation is to return disturbed areas back to their original condition as closely as possible.
2.0
There is mounting awareness of the need to implement engineering design for proposed borrow pits, roads and industrial sites to include landscaping, conservation and rehabilitation management to reduce the amount of unnecessary damage we cause to the environment.
This awareness is also expressed in the repair and rehabilitation of old borrow pits and disturbed sites to prevent erosion and promote the establishment of indigenous flora and a return of fauna communities (local plants and animals).
The need to reduce the visual impact of these disturbances is most important.
These guidelines and principles will fundamentally apply to most situations. Additional - requirements for contractors are defined under Section 12.0, Contractors - Borrow Pit Development and Rehabilitation Checklist. * -2-
3.0 SECTION A. PROPOSED PITS
3.1 PLANNING
Location, access, clearing and stockpiling of overburden and topsoil needs to be carefully planned to provide overall efficiency in both development and rehabilitation of disturbed sites. It must be recognised that situations will vary between sites. Areas of significance must be recognised and avoided, e.g. drainage systems, Aboriginal sites.
3.2 LOCATION AND ACCESS
Approval to open a borrow pit must be given by the Resource Development Department, Newman. A clearance must also be obtained from that Department for possible sites of Aboriginal significance.
Borrow pits are located where the required material is most readily and economically available. Borrow pit locations should avoid large trees or heavy stands of timber.
Placement of borrow pits should be out of sight of roadways and any prominent observation areas, with consideration being given to placement of borrow pits behind screens of vegetation or terrain. If this is not possible, then a buffer zone of vegetation at least 150 metres wide should be left between the road and the proposed borrow pit. Location of borrow pits could also be influenced by lease conditions and agreements with other lease holders.
The shape of the borrow pit will be longitudinal (see Figure 1) and will be operated parallel to any roads to further reduce visual impact.
Vehicle movement should be confined to a single access road to the borrow pit area to avoid additional unnecessary rehabilitation work. -3-
Figure 1 - Location and Access
3.3 WATERCOURSES
Watercourses should be avoided by at least 50 metres to ensure that natural flows of water are not impeded to any great degree, with the exception of sand extraction, which in the Pilbara would generally have to come from a major watercourse.
3.4 SIZE OF BORROW PITS
Borrow pit development will be a rectangular design and have a maximum dimension of 200 metres long by 50 metres wide (one hectare). Distance from any road would be at least 150 metres.
Where large quantities of material are required, then a series of borrow pits will need to be developed, with each pit being separated by a 50 metre undisturbed buffer zone (see Figure 2).
Borrow pits should conform with the natural contours and drainage systems of the area so that ecosystems associated with those drainage systems are not destroyed.
'I -4-
-4-200m F50 m 50 ) 154m + ACCEPTABLE
ROAD
DEVELOP 1ST TFIT 1 ] 4 50m PREFERRED
DEVELOP 2ND ,,J PIT 2 ] {
15Cm
ROAD
Figure 2- Borrow Pit Size and Location
3.5 CLEARING AND STOCKPILING OF OVERBURDEN AND TOPSOIL
Borrow pits should firstly be pegged to the determined amount of material required, but in any case be no greater than 200 metres x 50 metres in a single borrow pit.
Where the extent of material is not known, costeans can be dug to determine the material required. Unnecessary damage to vegetation should be avoided and costeans must be backfiled should they not be part of the borrow pit development.
Overburden, which is the vegetation cover should then be pushed off to the longitudinal sides of the intended borrow pit and left in a neat windrow for future use in rehabilitation (see Figure 3). Do not burn the overburden as this destroys organic material, seed and biological content beneficial for successful rehabilitation.
Topsoil to a depth of 100-150mm is then removed to the longitudinal sides of the borrow pit and left in a neat windrow. This topsoil also contains organic matter, seeds, nutrients and biological content. This operation can best be carried out by a dozer or front end loader. Overburden and topsoil on the access track should be pushed to one side of the track for use in the final rehabilitation phase of the access track. -5-
OVERBURDEN -* TOPSOIL
Ii
I Figure 3 - Overburden and Topsoil Stockpile
3.6 REMOVAL OF BORROW PIT MATERIAL
All operations are to be confined to the internal pit area and access is to be by a single track only, or in some instances for safety reasons, two tracks. The depth of the borrow pit should not exceed 1.5 metres.
4.0 ENVIRONMENTAL IMPACTS OF BORROW PITS
SHORT-TERM
Destruction of flora and fauna; dust generation; erosion; scar on the landscape; high density of pioneer plant species because of increased water collecting in the borrow pit; and increased activity of feral animals because of water ponding, which will increase the above impacts. -6-
LONG-TERM
Change of environment because of increased water collection in the borrow pit; time period for total or acceptable rehabilitation will be at least 10 years; and slow return of native fauna due to the absence of required vegetation communities and soil structures.
5.0 FUTURE USES OF BORROW PITS
Within Mt Newman Mining operations, there is little scope for future use of borrow pits other than for the extraction of further material where a pit has not been extracted to the allowable capacity. This requirement should be planned so that progressive extraction and rehabilitation can take place.
With our harsh environment and isolation there is little scope for developing borrow pits for any other uses, e.g. recreational uses.
6.0 SECTION B - REHABILITATION
6.1 INDUSTRIAL RUBBISH
Once extraction of material is completed all industrial rubbish should be deeply buried or removed for proper disposal.
The borrow pit floor should be left neat with any stockpiles of material being respread over the borrow pit floor.
6.2 LANDSCAPING
Borrow pit walls should then be pushed out or battered to blend closely with the surrounding environment, with a slope of not less than 3H:1V (3 horizontal to 1 vertical) (see Figure 4). .7-
B%
BEFORE LANDSCAPING
-
AFTER LANDSCAPING
Figure 4 - Landscaping
6.3 SPREADING TOPSOIL
The stockpiled topsoil is then spread over the borrow pit floor as evenly as possible (Figure 5).
Figure 5 - Spreading Topsoil
-8-
6.4 SPREADING OVERBURDEN
Stockpiled overburden is then spread evenly over the top of the topsoil.
6.5 RIPPING
Ground that has been compacted by the movement of equipment (trucks, loaders, etc.) within the borrow pit requires deep ripping, which breaks this compaction and allows water infiltration, seed lodging and plant root penetration.
Ripping must be worked along the contour to reduce the possibility of erosion. Ripped ground must not be driven over and should be left as rough as possible. This also helps to prevent people from driving into pits and damaging rehabilitation development. A windrow should be placed at the entrance of the borrow pit to prevent entry.
The final phase of rehabilitation is to spread stockpiled topsoil and overburden over the access track and then rip.
Rehabilitation of borrow pits and access tracks is not complete until ripping has been carried out.
6.6 SEEDING
Rehabilitation progress should be monitored and if necessary seeding of borrow pits may also need to be carried out. Seed used must be of the local surrounding species.
The Rehabilitation Officer is to be informed of all borrow pit rehabilitation completion so that this monitoring can be scheduled for action.
7.0 SECTION C - REHABILITATION - OLD BORROW PITS
Old borrow pits are those where material has been extracted with no attempt at landscaping or rehabilitation. These borrow pits are in various stages of revegetation, most of which are unsatisfactory and not of an acceptable standard.
-9-
It is therefore necessary to look at these borrow pits objectively and start from the beginning, regardless of vegetation establishment, unless the pits have been landscaped and the vegetation is acceptable.
During the following phases of rehabilitation, it is desirable that every attempt should be made to save as much established vegetation as possible.
7.1 LANDSCAPING
The sides of borrow pits are to be battered as per Section 6.2 of this manual. Every effort should be made to achieve a 3H:1V batter angle.
7.2 TOPSOIL AND OVERBURDEN
Topsoil and overburden from a depth of 100-150mm should then be removed from a strip no more than 10 metres wide from around the edge of the borrow pit and spread evenly over as much of the borrow pit as possible.
7.3 RIPPING
Ripping to contour is the final phase of rehabilitation. This includes the entire pit area together with that area from where the topsoil and overburden were removed. This operation allows for seed lodging, water infiltration and root penetration to promote rehabilitation success.
Access tracks to these borrow pits are then ripped to prevent entry and to promote regrowth.
7.4 OLD ROADS AND DISTURBANCES
Old unnecessary roads and all disturbed sites should be treated using the principles described in this manual to promote vegetation establishment and the removal of that scar on the landscape. - 10 -
8.0 SUPPLEMENTARY TREATMENTS
Monitoring of treated borrow pits is important and where necessary, seeding operations should be carried out. This monitoring is to be scheduled by the Rehabilitation Officer. Species used must be indigenous, that is those that are growing in the surrounding area. Current technology will determine seeding rates and treatments.
Rehabilitation technology to date does not indicate any need to apply fertilisers.
Water harvesting techniques are applied through the ripping to contour phase.
9.0 SUMMARY
It is important that we understand and preserve the environment to maintain a heritage for future generations.
It is more important that BHP Iron Ore Pty Limited and the employees of this company be equally concerned for the environment. With proper planning, management and rehabilitation of borrow pits as outlined in this manual, those objectives are possible.
10.0 BORROW PIT TECHNICAL DATA
Maximum Size (one Hectare) 200m x 50m Distance from Roads Minimum - 150 metres Distance between Pits Minimum - 50 metres Depth of Topsoil Recovery - 100-150mm Depth of Borrow Pits Maximum - 1.5 metres Depth of Spreading Topsoil/Overburden - Evenly over disturbed area Depth of Topsoil/Overburden Strip (Old Pits) - 100-150mm Width of Topsoil/Overburden Strip (Old Pits) - Maximum 10 metres Batter Angle - 3H:1V 11.0 PROPOSED BORROW PITS - PROGRESS WE CHECKLIST
Pit No. I Location - Date 1 - Approval to open borrow pit
2 - Aboriginal site clearance 3 - Planning Out of sight of prominent observation points Trees and heavy stands of vegetation preserved Screened behind vegetation belt or terrain 150 metre buffer zone from road Watercourses avoided Single access Borrow pit pegged - single pit - multiple pits Borrow pits longitudinal to major roads Maximum dimension 200m x 50m Minimum distance between pits 50m Maximum depth of pit 1.5m
4 - Overburden Stockpiled - longitudinal sides 5 - Topsoil Stockpiled - longitudinal sides Depth removed 100-150mm
6- Removal of Material Maximum depth 1.5m All activity inside pit area Access by single track
7 - Rehabilitation Industrial rubbish buried/removed Landscaping 3H: 1V Topsoil spread evenly Overburden spread evenly Ripping of entire pit and disturbance Ripping of access road Seed broadcasting
8 - Rehabilitation Passed By:
9 - Comments - 12 -
12.0 CONTRACTORS BORROW PIT DEVELOPMENT AND REHABILITATION CHECKLIST
It is the responsibility of the Contractor to obtain permission for removal of material from borrow pits and the opening of new borrow pits.
The following checklist is for progressive borrow pit operations and rehabilitation.
Approval for removal of material or permission to open a borrow pit - Contact Resource Development Department, Newman.
Pegging of area, defined access: Pit Dimensions: Area Max. 200m x 50m Depth Max. 1.5m
Overburden - Stockpiled.
Topsoil - Stockpiled Depth of removal 100-150mm.
Rehabilitation Industrial rubbish buried/removed Landscaping 3H:1V Topsoil spread evenly Overburden spread evenly Ripping of entire pit and disturbance Ripping of access road.
6. Rehabilitation checked by:
RESOURCE DEVELOPMENT ......
REHABILITATION OFFICER ......
On occasions one borrow pit may provide material for a number of contractors. In these cases records of material removed is required so that disputes about rehabilitation requirements can be resolved.
In all cases a record of material removed is to be lodged with the Resource Development Department in Newman.---- $EPTL OTCTOP 00 W;4LA :043Y R0,09 pTh