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Brockman Syncline 4 Mine Closure Plan April 2018 12. Biodiversity 12.1 Terrestrial fauna habitat There are four main habitat types identified at BS4. These habitats include hills and hilltops, plains and broad valleys, creek lines and flood plains, and gorges, gullies and free faces (Figure 19). Characteristics of these habitat types are provided in Table 12. Hilltops, gullies and creek habitats are of high value due to the diversity of microhabitats and potential to support conservation significant fauna species, while plain and valley habitats have lower value. In contrast, cleared habitat, created through mine disturbance, provides little food, shelter, water or any other life essential and is considered to have little to no habitat value. Table 12: Description of pre-mining habitats identified at BS4 Landform Basic description Hills and hilltops Hills, ridges, plateaux remnants, gorges and breakaways of varied geological origin. Soil is generally skeletal sandy clay loams with greater than 80% stony detrital material. Under natural conditions, this habitat is characterised by Eucalyptus leucophloia subsp. Leucophloia low open woodland over various Triodia species. Rocky, sheltered ridges and breakaways provide a suite of specialist plants or species more typical of lowlands. This habitat creates a diverse array of microhabitats and refugia. The habitat often contains rock shelters in the form of overhangs, cracks, crevices, caves and areas for water to pool during the wet season. Vegetation provides microhabitats in the form of logs, debris and hollows. This habitat zone will be present in undisturbed areas of the lease and may evolve around the edge of the disturbed areas, especially where the pit shell intersects local hills after erosion processes occur. However, the characteristics of this habitat are not compatible with the closure landform is unlikely to be restored or introduced as part of the rehabilitation activities. Gorges, gullies and Deep, often rocky gorges, with rocky structures providing large free faces opportunities of refuge and foraging for a wide suite of vertebrate fauna species; numerous rock ledges, crevices and caves. Very steep topography with an irregular surface with little exposed soil. The soil, when available, is sandy to sandy-clay or stony compact soils, low levels of leaf litter, sparse open vegetation; small caves and crevices, surface water present in some areas. The common dominant species mentioned in this habitat are Acacia aptaneura, A. citrinoviridis, A. pruinocarpa, Corymbia ferriticola, Dodonaea pachyneura, Eriachne mucronata (typical form), Eucalyptus leucophloia subsp. leucophloia, Grevillea berryana and Triodia epactia. This habitat zone will be present in undisturbed areas of the mine and may evolve around the edge of the disturbed mine area especially where the pit shell intersects local hills after erosion processes occur. However, this habitat type will not be restored or rehabilitated as part of the closure plan. This habitat creates a diverse array of microhabitats and refugia. The habitat often contains rock shelters in the form of overhangs, cracks, crevices, caves and areas for water to pool during the wet season. This habitat zone will be present in undisturbed areas of the lease. The characteristics of this habitat are not compatible with the closure landform is unlikely to be restored or rehabilitated as part of the rehabilitation activities. Page 39 Brockman Syncline 4 Mine Closure Plan April 2018 Landform Basic description Plains and broad Low and occasionally slightly undulating alluvial plains including outwash valleys areas and broad drainage basins. Under natural conditions, soils often consisting of sandy-clay soils covered by rocky lag gravel. The habitat is characterised by Eucalyptus leucophloia, E. gamophylla, Corymbia hamersleyana, A. pruinocarpa, A. inaequilatera and species in the A. aneura complex open woodland to sparse trees over Acacia spp., Eremophila spp., Ptilotus spp., Senna spp. and Solanum lasiophyllum open shrub land over Triodia spp. open hummock grassland. The habitat includes minor drainage lines, where T. longifolia, Gossypium robinsonii and A. ancistrocarpa are characteristic. This habitat type contains limited microhabitats with the dominant Acacia species providing no tree hollows, few logs, limited leaf litter and sparse vegetation. SRE invertebrate species usually comprise mygalomorph (trapdoor) spiders, scorpions, pseudoscorpions and isopods. Most SRE invertebrates prefer the southern foot slopes where sun exposure is reduced and the level of moisture under shrubs and trees is increased. This habitat zone will be present in undisturbed areas of the lease. Characteristics of this habitat may be suitable for rehabilitation planning and could be considered where there is the opportunity for deep soils to develop, i.e. on waste dumps. Creek line and flood A habitat that begins at the top of hills and runs to the surrounding plains, plains or encompasses small tributaries that eventually flow into larger river and major drainage habitat types. Surface water is more likely to persist in this habitat after it has evaporated elsewhere, providing a refuge for fauna. The creek habitat includes areas that are periodically flooded due to large surface water volumes (floodplains). The habitat is characterised by Eucalyptus leucophloia subsp. Leucophloia and Acacia shrub land over Triodia sp open hummock grassland, including the presence of weed species such as *Cenchrus ciliaris. Creek habitats act as wildlife corridors that help flora and fauna disperse across the landscape. There is a high diversity of microhabitats including logs, debris, tree hollows and soft soils, as well as temporary and permanent pools. This habitat zone will be present in undisturbed areas outside of the lease. It is likely that rehabilitation of some disturbed drainage line habitat will be required coincident with, or as part of, local drainage controls. It is possible that drainage line habitat could be introduced coincident to surface water runoff controls in the closure landform. Page 40 Brockman Syncline 4 Mine Closure Plan April 2018 Figure 19: Terrestrial fauna habitats of Brockman Syncline 4 Page 41 Brockman Syncline 4 Mine Closure Plan April 2018 12.2 Fauna reintroduction Re-introduction of fauna is not considered as part of this closure plan. Instead, natural migration of fauna species into rehabilitated land is encouraged by creating habitats with similar composition to pre-mining communities in appropriate locations and with consideration of the post-closure soil and landforms design. Habitat elements that are considered as part of the closure landform design include: • vegetation known to provide preferred food or shelter preference; • retaining and replacing woody debris; • rapid generation and retention of leaf litter using small-scale topography (e.g. furrows created from ripping); • introducing or leaving rocky features such as oversized waste burden or scree slopes; • creating greater depths of friable soil (or suitable mineral wastes) for burrowing fauna; • preserving connectivity with unmined areas, and maintaining the quality of these habitats; and • managing feral predators and herbivores across both reference and rehabilitated areas. Species associated with plains, drainage line or disturbed habitats have the potential to benefit from the rehabilitation of mine, due to returned or expanded habitat post-closure. 12.3 Conservation significant fauna Fauna survey coverage is shown in Figure 20 and Table 13 lists the significant fauna that were found within the BS4 area prior to disturbance activities. Seven species of conservation significance have been recorded to date in the study area, with evidence of the Northern Quoll ( Dasyurus hallucatus ) found adjacent to the study area. The Pilbara leaf-nosed bat ( Rhinonicteris aurantia ) is present in the BS4 area. Audio calls of PLNB indicated the presence of a roost in the Brockman area, prompting further targeted surveys throughout 2015, 2016 and early 2017. A PLNb roost (the Upper Beasley River Roost (UBRR)) was confirmed in the Brockman ridge to the north of deposits M and N. A nearby pool (Ridge Pool) was identified as being important to the bats using the roost. An additional pool (Plunge Pool), also considered important to the bats using the roost, was identified to the east of BS4 MM Deposit M. Currently both Deposits M and N are proposed as AWT only, with investigations ongoing into the potential impact of dewatering these deposits on the pools. Early work identified the Rhagada sp Mt Brockman land snail which was thought to be unique. This triggered an approval condition for the site (Condition 8 of MS 717) to implement a Snail Management Plan during operations to protect the species and further develop knowledge on it. Further testing and sampling determined that the snail was not endemic to the area, resulting in the plan becoming redundant. MS717 was superseded by MS1000, with no further requirements to manage Rhagada sp Mt Brockman . A total of 19 sites have been sampled for stygofauna, despite this sampling effort, no stygofauna have been recorded from the study area to date and there is no evidence of a diverse or sizable stygofauna population at BS4. This finding is consistent with previous studies in the locality and if taken together with site related factors such as a relatively deep-water table, this suggests that it is unlikely that an abundant or diverse stygal community