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Iluka Resources Limited Vegetation and Fauna Management Plan Gingin Mineral Sands Project March 2006


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Iluka Resources Limited
Vegetation and Fauna Management Plan
Gingin Mineral Sands Project
March 2006




Table of Contents




1 Introduction 1

1.1 Objective 1



2 BASELINE VEGETATION AND FAUNA STUDIES 1

2.1 Vegetation 1

2.2 Fauna 1

3 vegetation disturbance 2

3.1 Management of cleared Vegetation (green waste) 3



4 Rehabilitation 3

4.1 Fauna protection and habitat restoration 3

4.2 Rehabilitation Monitoring 4

5 dieback and weed management 4

6 SOUTH AND NORTH STREAMS 4

6.1 Construction of Diversions 4

6.2 Clearing Riparian Vegetation 5

6.3 Soil Management 5

6.4 Recreating Streamlines 5

6.5 Rehabilitating Streamlines 6

6.6 Management of Downstream Impacts 6

7 Central Wetland 7

7.1 Control of Flows 7

7.2 Clearing Riparian Vegetation 7

7.3 Soil Management 7

7.4 Recreating the Wetland 7

7.5 Rehabilitating the Wetland 7

7.6 Management of Downstream Impacts 7

8 Upstream North Stream Restoration 8

9 Performance Criteria and monitoring 8

10 catchment support 10

11 References 10

12 Document control 11


Table of Tables

Table 1: Disturbance Requirements 2

Table 2: Performance Criteria 8

Table of Plates

Plate 1: Stabilising a flow channel 5

Plate 2: Meanders in a created stream 6

Table of Figures

Figure 1: Vegetation

Figure 2: Clearing Requirements

Figure 3: Area of Disturbance

Figure 4: Rehabilitation

Figure 5: South Stream Diversion

Figure 6: North Stream Diversion


1Introduction


The mining of the Gingin mineral sands deposit involves the clearing of pastoral land and some native vegetation. This management plan outlines the procedures for minimising impacts on vegetation and fauna.

1.1Objective


The objective of this Management Plan is to maintain the abundance, diversity, geographic distribution and productivity of flora and fauna at species and ecosystem levels through the avoidance or management of adverse impacts and improvement of knowledge.

2BASELINE VEGETATION AND FAUNA STUDIES

2.1Vegetation


Mattiske Consulting Pty Ltd undertook a flora and vegetation survey of the Project Area in September 2001 and July 2004. The findings of this survey (Mattiske Consulting Pty Ltd, 2001; Mattiske Consulting Pty Ltd, 2004) are summarised below.

No Declared Rare or Priority Flora species, pursuant to Subsection 2 of Section 23F of the Wildlife Conservation Act 1950 and listed by the Department of Conservation and Land Management (CALM) (2000), were located during the survey. No endangered or vulnerable species pursuant to s178 of the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) were located during the survey.

Five eucalypt woodland remnant communities and one melaleuca woodland remnant community were identified during the survey (Figure 1). The area has been largely cleared and grazed with only the occasional native tree and understorey species persisting within each community.

No Threatened Ecological Communities pursuant to Schedule 2 of the EPBC Act were located and none of the plant communities identified during the survey are classified as either regionally or locally significant.

It is considered likely that Phytophthora cinnamomi (Jarrah dieback disease) is present in the Project Area, but the low number of native plants and the high density of weed species within the survey area limited any assessment of extent and severity. In view of the degree of disturbance of the vegetation, a more specific survey is unwarranted.

None of the weed species identified during the survey are Declared Plants in the Gingin area. Two of the weed species found within the Project Area, Solanum linneanum (Apple of Sodom) and Zantadeschia aethiopica (Arum Lily), are classified as Declared Plants in southern areas of the State, but not in the vicinity of Gingin.

Although not present during the Mattiske survey, the declared weed Echium plantagineum (Patersons Curse) is present on the site.

2.2Fauna


GHD Pty Ltd conducted a fauna survey of the Project Area in March 2004. A total of 20 bird species, no fish species, no amphibian species, five mammal species (in addition to livestock) and three reptile species were observed. No aquatic fauna was found in the creeklines surveyed.

No rare or priority fauna species were observed during the survey. The EPBC Act Protected Matters and CALM Databases listed the following rare and priority species for the general Gingin area, Calyptorhynchus baudinii (Baundin’s Cockatoo), Calyptorhynchus latirostris (Carnaby’s Cockatoo), both schedule 1 species and Haliaeetus leucogaster (White-bellied Sea-eagle), listed as vulnerable.

Although not observed, the Cockatoos may feed on Marri nuts in the Project Area on occasion, however given the degraded nature of the bush areas in the Project Area, they are more likely to be seen flying overhead, in search of more suitable feeding habitat. The White-bellied sea-eagle is not considered likely to be observed in the Project Area, as it is 40 km from the coast, the Sea-eagle’s preferred habitat. None of the bird species identified in the Project Area are rare or priority species.

Four of the five mammal species observed were introduced species, the Vulpes vulpes (Red Fox), Oryctolagus cunuculus (European Rabbit), Mus musculus (House Mouse) and Rattus norvegicus (Brown Rat). The native mammal was the Macropus fuliginous (Western Grey Kangaroo).

The extensive clearing of the Project Area and its use for grazing has led to disjunct and degraded habitats. The lack of understorey leads to a reduced fauna presence. Rabbits, foxes, mice, rats, a gwardar (Western Brown snake) and skinks were all observed in the vicinity of derelict dwellings which provided shelter, although rabbits were also observed in the area of Xanthorrhoea vegetation in the east of the Project Area. The remaining vegetation was limited in habitat value. Potential bird and marsupial nesting sites were occupied by feral bees and while there were nectar resources present in the form of flowering Marri trees, there was a lack of understorey to provide shelter between Marri stands, limiting use of the resource to birds and feral bees.

There are no vegetation corridors on the site to provide a link between the plateau and the coastal plain. Better linkages are found along more heavily vegetated Brooks to the north and south of the Project Area.

The only fauna found in the north stream was two backswimmers and one diving beetle. One Brown Rat was observed in overhanging Melaleuca branches crossing the creek, however no birds were seen. Several decomposed livestock carcasses were observed along the creekline. Filamentous algae, Azolla and grass were found in the creek. No deep pools, which may have provided habitat for fish and amphibians, were found. A winter-wet dampland on the site may be utilised by winter feeder birds such as Ibis and some duck species, however the dampland is not considered a drought refuge to migratory birds during summer (GHD, 2004).

3vegetation disturbance


The total area of disturbance will be approximately 280 ha (see Figure 2). A break down of clearing is shown in Table 1.

While the Project Area has been largely cleared and grazed with only the occasional native tree and understorey species persisting within each community (Mattiske, 2001), 8.1 ha of the 280 ha to be disturbed were classified as native vegetation by the Department of Agriculture. This area was approved for clearing by the Department of Agriculture on 29 April 2004. These areas are shown on Figure 3.

In addition, isolated trees in paddocks and other areas not classified as native vegetation by the Department of Agriculture will be cleared.

Table 1: Disturbance Requirements



Description

Area (hectares)

PITS

Includes pits, roads, noise bunds, stream diversions, stockpiles.



140 ha

SOLAR DRYING DAMS

Includes 64 ha located on mine pits.



174 ha minus 64 ha cleared for pits = 110 ha

INFRASTRUCTURE

Includes concentrator area, pipelines, process water dam, return water dam, screenplant, conveyor, miscellaneous infrastructure.



30 ha

TOTAL DISTURBANCE

280 ha

Millable and firewood timber will be removed from site for use. A proportion of the vegetation cleared during the Project development will be stockpiled for use in rehabilitation. Grasstrees will be salvaged where possible.

The Project will be designed, constructed and operated to minimise the impacts on remnant vegetation by:



  • avoiding clearing of native vegetation where possible, particularly of large trees;

  • defining the area to be cleared on maps and supervising clearing activities (see Figure 2);

  • confining temporary work areas to previously disturbed areas, where practicable;

  • parking vehicles and machinery in designated areas;

  • ensuring that effective dust control measures are implemented;

  • retaining topsoil, subsoil, root stock and cleared vegetation in designated areas for use in rehabilitation;

  • progressively rehabilitating and monitoring disturbed areas with native vegetation where appropriate; and

  • raising the awareness of the workforce about conservation issues through environmental awareness training.

3.1Management of cleared Vegetation (green waste)


Green waste includes trees, bushes and undergrowth generated from clearing activities. Green waste will be utilised where possible, to minimise the amount of waste requiring disposal.

Grasstrees will be salvaged where possible. Millable and firewood timber will be removed from site for use. A proportion of the vegetation will be mulched or chipped and stockpiled for use in rehabilitation.

Green waste that cannot be milled, mulched or chipped due to excessive sand, rock or other impediment, will be stacked and burnt.

4Rehabilitation


    As described in EMP-005 Decommissioning and Closure Management Plan, post mining, 8.1 hectares of cleared native vegetation will be restored. The restored vegetation will include understorey species not currently present and the area of rehabilitation will be expanded to over 12 ha (Figure 4). In addition, local provenance species will be utilised and the area of rehabilitation will be fenced off to exclude livestock.

    Areas of pasture will be rehabilitated by:



  • recreating soil profile through the return of topsoil and subsoil to disturbed areas;

  • adding clay fines to the subsoil to improve soil fertility and moisture retention;

  • implementing seeding, fertilising and weed control farming practices as appropriate; and

  • conducting productivity monitoring to assess the success of rehabilitation.

4.1Fauna protection and habitat restoration


    The lack of understorey present within the Project Area leads to a reduced fauna presence (GHD, 2004). However, impacts on existing fauna habitat will be minimised as per the actions prescribed in section 3 to minimise disturbance of native vegetation. In addition, the following management actions will be implemented to minimise impacts on fauna:

  • no firearms will be allowed on site;

  • no domestic pets will be allowed on site; and

  • tailings dams are checked at least once per shift. As far as practicable, these checks will incorporate checks for the presence of any animals trapped within the sediment.

Post mining rehabilitation of native vegetation as described in section 4 will provide habitat for fauna.

4.2Rehabilitation Monitoring


As described in EMP-005 Decommissioning and Closure Management Plan the success of pasture and native rehabilitation will be monitored for approximately 3 years following mining to ensure that the required outcomes are achieved.

5dieback and weed management


    Phytophthora cinnamomi (Jarrah dieback disease) is more than likely present in the soil and there is a high density of weed species in the Project Area. There is a very limited opportunity for dieback or weeds to have any more of an adverse effect (Mattiske Consulting Pty Ltd, 2001). Therefore vehicle hygiene procedures to limit the spread of dieback and introduced species within the Project Area are not warranted. However, machinery at the site will be thoroughly washed down prior to being transported to any areas in Western Australia susceptible to dieback, but where the fungus is not already known to be present. Likewise, machinery will be thoroughly washed down prior to transportation to any areas in Western Australia where the weed species present in the Project Area are declared elsewhere in the State. Solanum linneanum is a Declared Plant in the District of Jerramungup and in the Albany, Busselton, Manjimup and Harvey regions; Zantadeschia aethiopica is a Declared Plant in the Albany, Busselton, Manjimup and Harvey Regions. Iluka will liaise with the Department of Agriculture regarding the management of Solanum linneanum (Apple of Sodom) and Zantadeschia aethiopica (Arum Lily).

    Inspections will be conducted during germination time for exotic species such as Paterson’s Curse (Echium plantagineum). Where detected, these species will be controlled by the use of herbicides.


6SOUTH AND NORTH STREAMS

6.1Construction of Diversions


The diversions will be constructed sequentially with the mining operations. The first stage will be to develop a drainage channel along the eastern side of the pit. This will divert overland flow into the South and North stream diversions. The south stream diversion will be created first and direct waterflow around the edge of the mining area and return to the original watercourse at the Dewar Road crossing (Figure 5). The north stream diversion will be created as mining advances to the north. Flow will be diverted around the edge of the mining area and return to the original watercourse at the Brand Highway crossing (Figure 6).

The diversion channels will be stabilised with either existing pastoral species, geotextile fabrics or oversize from the mining operation where needed to minimise the potential for erosion.





Plate 1: Stabilising a flow channel

The North and South stream diversions will be constructed and vegetated to minimise erosion and preserve streamflow resources. The area and hydrologic characteristics of the resulting diversion catchments is similar to the existing stream catchment and should not increase flows or change the hydrologic characteristics of the streams downstream. The diversion channels are trapezoidal in shape and have been designed to contain a 1 in 50 year rainfall event.


6.2Clearing Riparian Vegetation


Once the diversion channel is in place vegetation along the streams will be cleared to allow mining. Vegetation will be cleared along the streams as outlined in Section 3 above.

6.3Soil Management


The soil beneath the north and south streams is fine to coarse alluvium. The topsoil is up to approximately 150 mm in depth. The overburden occurs from approximately 150-5000 mm in depth and is a fine to coarse alluvium/grey clay and at 5000 to 8000 mm is a grey siltstone/mottled sandstone.

EMP-002 Soil Management Plan describes the way these soils will be handled in the mining and rehabilitation processes and describes the management actions that will be taken to attempt to preserve the structure of these soils.


6.4Recreating Streamlines


Following mining the streams will be recreated along their original alignment. The diversion channels will not be removed until the recreated channel is in place and stabilised such that flows will not cause erosion.

The recreated stream zone with have low and high flow zones and incorporate gentle meanders consistent with the flow alignments of similar sized streams in the district. Erosion control measures will include grassing of the watercourse and use of erosion matting.





Plate 2: Meanders in a created stream

Water quality and quantity upstream and downstream of the mining areas will continue to be monitored during the rehabilitation phases (as described in EMP-004 Water Resources Management Plan).


6.5Rehabilitating Streamlines


Both streams will be fenced from grazing stock and include stock watering points and crossings. These will be designed in accordance with the Water Notes relating to livestock crossings and watering points (WRC, 2000a; WRC, 2000b). Assistance will be sought from the Gingin LCDC and the DoE in rehabilitating the streams.

Revegetation will consist of species existing prior to mining activity, plus other native understorey species. Species for revegetation will be selected by reviewing other sections of stream vegetation in the area and through advice from the Gingin LCDC.

Areas for rehabilitation are shown in Figure 4.

6.6Management of Downstream Impacts


The North and South streams immediately downstream of the mine area support degraded riparian vegetation. This vegetation is likely to rely on streamflow and groundwater baseflow to sustain current ecological functions. The catchment areas for the North and South streams will remain about the same, and hence flow regimes will not be significantly changed during the diversion. Modelling shows that predicted monthly flows for the North and South streams are similar before and during mining, while predicted runoff hydrographs for a 50-year, 90-minute recurrence storm before and during mining are also similar.

Erosion currently present in the North Stream (below the Brand Highway crossing) and in the South Stream (below the Dewar Road crossing) outside the Iluka properties and downstream of the Project Area is not expected to be exacerbated by the diversion works as the flow regimes will not be significantly changed. Water quality and quantity will continue to be monitored upstream and downstream of the Project Area as outlined in EMP-003 Stormwater and Drainage Management Plan. This monitoring includes regular analysis of Total Suspended Solids and Turbidity upstream and downstream of the diversion points.


7Central Wetland

7.1Control of Flows


Water flows from the central wetland currently flow along a drainage channel referred to as the Central stream. A large area is seasonally inundated and there is no clearly defined flow path. The wetland will be mined and flows will be eliminated.

The clean water dam is proposed to be located on the Central stream. An existing farm dam will be upgraded for this purpose.

The clean water dam will be put in place prior to topsoil stripping and subsoil and overburden removal of the wetland area. This will prevent surface water from disturbed areas leaving the Project Area.

7.2Clearing Riparian Vegetation


The pre-mining area classified as vegetation and wetland covers approximately 0.2 hectares. The wetland contains a single species, Melaleuca preissiana. Once the clean water dam is in place, vegetation will be cleared to allow mining. Vegetation will be cleared along the streams as outlined in Section 3 above.

7.3Soil Management


The soil beneath the central wetland is deep pale grey sand. The topsoil is up to approximately 300 mm in depth. The pale grey sand subsoil is found at approximately 300-3500 mm in depth and the overburden is found at approximately 3500 to 8000 mm in depth and is a grey siltstone/mottled sandstone.

EMP-002 Soil Management Plan describes the way these soils will be handled in the mining and rehabilitation processes and describes the management actions that will be taken to attempt to preserve the structure of these soils.


7.4Recreating the Wetland


The post-mining contours will be landscaped to reflect the pre-mining contours and to recreate the wetland and Central Stream.

7.5Rehabilitating the Wetland


The wetland will be recreated with an upper storey of Melaleuca preissiana. A selection of understorey species will be planted based on other less degraded Melaleuca preissiana wetlands in the surrounding area and with advice from the Gingin LCDC. The wetland will be fenced to exclude stock.

7.6Management of Downstream Impacts


The main impact of the proposed mining and associated diversion drains will be to reduce or eliminate natural flows in the Central Stream. Disturbance by mining of the wetland will result in a net reduction in yields in the Central Stream by an estimated 340,000 kL/annum.

The Central stream west of the Brand Highway has been cleared and grazed and no longer supports riparian vegetation. Downstream impacts on riparian vegetation due to reduced surface water flows from upstream are not likely to be significant. The pasture species are likely to source water from the moisture within the soil.

Gingin Brook runs through the town of Gingin, southeast of the mine area, then braids into a series of channels, lakes, wetlands and swamps to the southwest and west. Some of this area is classified as “Conservation” and “Lakes Policy Area – DoE 6/95” by the DoE. All the streams in the proposed mine area discharge toward these wetland areas and ultimately into Gingin Brook. The reduced flows in the Central Stream is not expected to have any impact on the downstream riparian vegetation and wetland areas associated with the Gingin Brook because the volume of flow is insignificant compared to the volume received via Gingin Brook. The catchment for these downstream areas is in the order of 342 km2, more than 100 times larger than the mine area.

8Upstream North Stream Restoration


In addition to the rehabilitation of those areas disturbed by mining, the North stream will be fenced off for a further 1 km upstream on the Iluka owned property (Figure 4). The area will be infill planted with native species and a weed control program implemented. This will be an ongoing program during operations and rehabilitation.

It is anticipated that these improvements will enhance the post-mining environment and encourage a more diverse flora and fauna population.


9Performance Criteria and monitoring


The following table summarises the performance criteria for the activities outlined in sections 6 to 8 above. The criteria are defined as a series of actions to be completed for each rehabilitation area.

Table 2: Performance Criteria

Area

Action

Predicted Outcome

North Stream

Plant a range of endemic riparian understorey species (minimum of 5 species).

Increase the diversity of species.

North Stream

Fence either side of the reconstructed streams to eliminate stock grazing.

Improved establishment and growth of plants and reduced erosion of stream beds.

North Stream

Construct one stock crossing.

Stock access to water and across stream with minimal damage.

South Stream

Plant a range of riparian understorey species (minimum of 5 species).

Increase the diversity of species.

South Stream

Fence either side of the reconstructed streams to eliminate stock grazing.

Improved establishment and growth of plants and reduced erosion of stream beds.

South Stream

Construct one stock crossing.

Stock access to water and across stream with minimal damage.

Central Wetland

Plant a range of understorey species suitable to the wetland (minimum of 5 species).

Increase the diversity of species.

Central Wetland

Fence the reconstructed wetland to eliminate stock grazing.

Improved establishment and growth of plants and reduced erosion of stream beds.

Overall

Fence 12 hectares of streamline, wetland and tree belts.

Increase in vegetation from 8.1 ha cleared to 12 ha overall.

Agricultural Rehabilitation

Post-mining agricultural productivity similar to or higher than pre-mining productivity.

Similar or higher agricultural productivity.

Monitoring will need to continue until positive trends emerge which indicate that no further management of vegetation (both pasture and native), water resources and landform is required than would be necessary for similar properties in the area.

Ongoing maintenance of the rehabilitation will be conducted. This may include:



  • modification or maintenance of drainage and erosion control structures;

  • application of fertiliser;

  • planting of additional seedlings, supplementary seed application;

  • weed control measures;

  • repair of erosion or subsidence; or

  • repairing fencing.

10catchment support


A revegetation scheme supporting the restoration of the surrounding catchments has been proposed as an offset for mining the resource enhancement category wetlands. The scheme will actively sponsor:

  • Fencing of wetlands and waterways from stock;

  • Planting of riparian vegetation to maintain or enhance wetland values; and

  • Planting of native vegetation in degraded areas to enhance biodiversity.

In developing the scheme, Iluka will work closely with the Shire of Gingin and local landcare groups in order to complement their catchment restoration activities.

11References


Mattiske Consulting Pty Ltd (2001) Flora and Vegetation Survey Proposed Mineral Sands Mine Gingin October 2001. Prepared for URS.

Mattiske Consulting Pty Ltd (2004) Flora and Vegetation Survey Proposed Mineral Sands Mine Gingin August 2004. Prepared for Iluka Resources.

GHD (2004) Fauna Survey, Gingin. Prepared for Iluka Resources.

WRC (2000a) Water Notes 06: Livestock Management: Construction of Livestock Crossings, Water and Rivers Commission, Jan 2000.

WRC (2000a) Water Notes 07: Livestock Management: Watering Points and Pumps, Water and Rivers Commission, Jan 2000.

EMP-002 Soil Management Plan

EMP-003 Stormwater and Drainage Management Plan

EMP-004 Water Resources Management Plan

EMP-005 Decommissioning and Closure Plan

12Document control


Version

Changes

Date

0.1

Version submitted for government review

26/11/2004

0.2

Changes to document control and minor document changes

30/12/2004

0.3

Document reviewed against current practices. No changes to the content of the document.

01/03/2006











Figure 1: Vegetation

Figure 2: Clearing Requirements

Figure 3: Area of Disturbance

Figure 4: Rehabilitation

Figure 5: South Stream Diversion

Figure 6: North Stream Diversion




EMP-001 Vegetation and Fauna Management Plan

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