Metro Mining Appendix H2 - Metro Mining Community and Metro Mining Metro Mining Social Responsibility Policy Chapter 6 - Marine Ecology Bauxite Hills Project Environmental Impact Statement
Environmental Impact Statement
Table of Contents
6 Marine Ecology ...... 6-1 6.1 Project Overview ...... 6-1 6.2 Regulatory Framework ...... 6-1 6.2.1 Environment Protection and Biodiversity Conservation Act 1999 ...... 6-2 6.2.2 Nature Conservation Act 1992 ...... 6-2 6.2.3 Environmental Protection Act 1994 ...... 6-2 6.2.4 Coastal Protection and Management Act 1995 ...... 6-2 6.2.5 Fisheries Act 1994 ...... 6-3 6.3 Objectives and Performance Outcomes ...... 6-3 6.3.1 Protection Objectives...... 6-3 6.3.2 Performance Outcomes ...... 6-3 6.4 Assessment Method ...... 6-4 6.4.1 Marine Development Footprint ...... 6-4 6.4.2 Desktop Assessment ...... 6-8 6.4.3 Field Surveys ...... 6-8 6.5 Existing Environmental Values...... 6-9 6.5.1 Coastal Habitats ...... 6-12 6.5.2 Benthic Habitats ...... 6-19 6.5.3 Commonwealth Marine Area ...... 6-22 6.5.4 Conservation Significant Species ...... 6-26 6.5.5 Fisheries ...... 6-36 6.6 Potential Impacts ...... 6-37 6.6.1 Marine Habitats ...... 6-38 6.6.2 Marine Species ...... 6-42 6.6.3 Marine Pests ...... 6-45 6.6.4 Fisheries ...... 6-46 6.6.5 Summary of Impacts to Marine Ecology ...... 6-47 6.7 Cumulative Impacts ...... 6-48 6.7.1 Predicted Cumulative Impacts ...... 6-49 6.8 Management and Mitigation Measures ...... 6-51 6.8.1 Management of Impacts ...... 6-51 6.8.2 Matters of State Environmental Significance ...... 6-56 6.9 Qualitative Risk Assessment ...... 6-70 6.10 Summary...... 6-73 6.11 Commitments ...... 6-75 6.12 ToR Cross-reference ...... 6-76
List of Figures
Figure 6-1 Barge Loading Facility and infrastructure ...... 6-6 Figure 6-2 Indicative OGV anchorage area and reef habitat ...... 6-7 Figure 6-3 Bathymetry of Skardon River (September 2009) with bed features noted ...... 6-11 Figure 6-4 Skardon River marine vegetation and seagrass habitats ...... 6-17 Figure 6-5 Skardon River wetland classification ...... 6-18 Figure 6-6 Seagrass survey of the Skardon River entrance (Chartrand and Thomas, 2010) ...... 6-20 Figure 6-7 West Cape York Commonwealth Marine Reserve ...... 6-22 Figure 6-8 North Marine Region area ...... 6-26
i Bauxite Hills Project Marine Ecology
List of Tables
Table 6-1 Regional ecosystems within the Skardon River - marine vegetation ...... 6-12 Table 6-2 Vegetation of the Skardon River (adapted from Roelofs et al., 2002) ...... 6-14 Table 6-3 Benthic habitat surveys undertaken from the Skardon River (1986-2015) ...... 6-19 Table 6-4 Percentage cover from the Skardon River, anchorage options and a nearshore reef patch ...... 6-21 Table 6-5 Conservation status listed species that are known to occur or likely to occur ...... 6-27 Table 6-6 Listed marine species considered unlikely to occur ...... 6-28 Table 6-7 Number of turtle nesting tracks at four beach regions along western Cape York (modified from Bell, 2004) ...... 6-31 Table 6-8 Incidental snubfin dolphin sightings by PaCE in waters surrounding the Skardon River ...... 6-34 Table 6-9 MSES as they apply to the Bauxite Hills Project ...... 6-56 Table 6-10 Assessment against significant impact criteria: Flatback Turtle ...... 6-60 Table 6-11 Assessment against significant impact criteria: Green Turtle ...... 6-61 Table 6-12 Assessment against significant impact criteria: Hawksbill Turtle ...... 6-62 Table 6-13 Assessment against significant impact criteria: Loggerhead Turtle ...... 6-63 Table 6-14 Assessment against significant impact criteria: Olive Ridley Turtle ...... 6-64 Table 6-15 Assessment against significant impact criteria: three sawfish species and Speartooth Shark .... 6-65 Table 6-16 Assessment against significant impact criteria: Narrow Sawfish ...... 6-67 Table 6-17 Assessment against significant impact criteria: Estuarine Crocodile ...... 6-67 Table 6-18 Assessment against significant impact criteria: Dugong ...... 6-68 Table 6-19 Assessment against significant impact criteria: Australian Snubfin Dolphin and Indo-Pacific Humpback Dolphin ...... 6-69 Table 6-20 Assessment against significant impact criteria: Coastal Manta Ray ...... 6-70 Table 6-21 Qualitative risk assessment - marine ecology ...... 6-70 Table 6-22 Commitments – marine ecology ...... 6-75 Table 6-23 ToR cross-reference – flora and fauna ...... 6-76
List of Plates
Plate 6-1: Typical saltmarsh (foreground) and mangroves (rear) ...... 6-13 Plate 6-2: Mangrove community in Project area ...... 6-14
ii
6 Marine Ecology
This chapter identifies the key marine habitats, species of significance and sediment and water quality characteristics within the Bauxite Hills Project (the Project) area. Potential impacts are assessed in this chapter along with management and mitigation measures to reduce the identified potential impacts. The technical marine ecology report, prepared by Ports and Coastal Environment (PaCE), can be found in Appendix B3 – Marine Ecology Technical Report. 6.1 Project Overview
Aldoga Minerals Pty Ltd (Aldoga), a 100% owned subsidiary of Metro Mining Limited (Metro Mining), proposes to develop the Project located on a greenfield site on the western coastline of Cape York, Queensland, approximately 35 kilometres (km) northeast of Mapoon. The Project will include an open cut operation, haul roads, Barge Loading Facility (BLF), Roll on/Roll off (RoRo) facility, transhipping and will produce and transport up to 5 million tonnes per annum (Mtpa) of ore over approximately 12 years. The mine will not be operational during the wet season.
The Project is characterised by several shallow open cut pits that will be connected via internal haul roads. The internal haul roads will be connected to a main north-south haul road that will link with the Mine Infrastructure Area (MIA), BLF and RoRo facility located to the north of the pits on the Skardon River. Bauxite will be screened in-pit and then hauled to the product stockpile using road train trucks.
Bauxite from the Project is suitable as a direct shipping ore product (i.e. ore is extracted and loaded directly to ships with no washing or tailings dams required). Bauxite will be transported by barge via the Skardon River to the transhipment site, approximately 12 km offshore, and loaded into ocean going vessels (OGVs) and shipped to customers. No dredging or bed-levelling for transhipping is proposed as part of this Project.
OGVs of between 50,000 to 120,000 tonne (t) each will be loaded at the transhipment anchorage site. Vessels will be loaded and bauxite will be transported to OGVs 24 hours per day with barges having an initial capacity of approximately 3,000 t to meet early production volumes, increasing up to 7,000 t as the Project reaches a maximum production volume of 5 Mtpa.
The construction of the mine is due to commence in April 2017 and is expected to take seven months to complete. The first shipment of bauxite is planned for October 2017. The Project will be 100% fly-in fly-out (FIFO) due to its remote location. The Project will operate over two 12 hour shifts per day for approximately eight months of the year and is expected to employ up to 254 employees during peak operations. In addition to the workforce, it is expected that the Project will result in the employment of additional workers through local and regional businesses servicing the accommodation camp and the construction and operation of the mine. 6.2 Regulatory Framework
The protection of the marine environment is governed by several legislative acts including Commonwealth and Queensland State legislation. Those with relevance to the Project activities include:
. Environment Protection and Biodiversity Conservation Act 1999 (Cth);
. Nature conservation Act 1992;
6-1 Bauxite Hills Project Marine Ecology
. Environmental Protection Act 1994
. Coastal Protection and Management Act 1995; and
. Fisheries Act 1994.
Under the Queensland Marine Parks Act 2004 there are three designated State marine parks, however none of these occur in the Gulf of Carpentaria.
6.2.1 Environment Protection and Biodiversity Conservation Act 1999
The Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) provides a framework to protect and manage nationally and internationally important flora, fauna and ecological communities (among other things) as defined under the act as Matters of National Environmental Significance (MNES). Under the EPBC Act the Department of the Environment (DotE) has jurisdiction over actions that are likely to have a significant impact on MNES.
6.2.2 Nature Conservation Act 1992
The NC Act provides for the protection and management of native wildlife and habitat that support native species with particular regard to:
. Activities that may cause disturbance (that is tamper, damage, destroy, mark, move or dig up) to animal breeding places; and
. The taking of fauna.
Subordinate legislation, such as the Nature Conservation (Wildlife) Regulation 2006, lists protected species and areas to which the regulatory provisions of the NC Act apply including. This Regulation lists terrestrial and aquatic plant and animal species presumed extinct, endangered, vulnerable, rare, common, international or prohibited. It recommends management objectives for the protection and maintenance of these species in Queensland, as appropriate.
6.2.3 Environmental Protection Act 1994
The Environmental Protection Act 1994 (EP Act) has a broad objective of achieving sustainable development within Queensland. The subordinate EP Regulation defines Category A and Category B environmentally sensitive areas (ESAs). Category A ESAs include national parks, marine parks, the Great Barrier Reef region and the wet tropics area. Category B ESAs include some classes of protected areas, endangered regional ecosystem (RE) types, declared fish habitat areas and areas subject to international conventions.
6.2.4 Coastal Protection and Management Act 1995
The Coastal Protection and Management Act 1995 (CPM Act) provides for the protection, conservation, rehabilitation and management of the coast, including its resources and biological diversity. The CPM Act acknowledges the goal, core objectives and guiding principles of the National Strategy for Ecologically Sustainable Development (ESD) in the use of the coastal zone.
An approval for tidal works will be required under the CPM Act. Works associated with the proposed BLF may include construction within tidal areas and the disposal of excavated material within tidal areas. This will also include the construction of the loading berth located outside the Skardon River in the Gulf of Carpentaria.
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6.2.5 Fisheries Act 1994
The main purpose of the Fisheries Act 1994 is to provide for the use, conservation and enhancement of the fish resources and habitats as a way to apply and promote the principles of ESD. It regulates the taking and possession of specific fish, removal of marine vegetation, the control of development in areas of fish habitat and lists noxious fish species.
An approval is likely to be required to remove mangroves for the construction of the BLF under this Act. 6.3 Objectives and Performance Outcomes
6.3.1 Protection Objectives
As per the Terms of Reference (ToR) the protection objectives relevant to this chapter are:
. The activity is operated in a way that protects the environmental values of associated marine flora and fauna;
. Choice of the site, at which the activity is to be carried out, minimises serious environmental harm on areas of high conservation value and special significance and sensitive land uses at adjacent places;
. Location for the activity on a site protects all environmental values relevant to adjacent sensitive use;
. Avoids significant residual impacts to matters of national and state environmental significance; mitigates impacts where they cannot be avoided and offsets any residual impacts; and
. The activity is developed and operated in a way that avoids environmental harm including impacts on marine environmental values.
6.3.2 Performance Outcomes
The performance outcomes for the protection of the marine environment are based on Schedule 5, Tables 1 and 2 of the Environmental Protection Regulation 2008:
. Activities that disturb flora and fauna will be managed in a way that prevents or minimises adverse effects on the environmental values of the marine environment;
. The activity will be managed to prevent or minimise adverse effects on the environmental values of land due to unplanned releases or discharges, including spills and leaks of contaminants;
. Areas of high conservation value and special significance likely to be affected by the proposal are identified and evaluated and any adverse effects on the areas are minimised;
. The activity, and components of the activity, are carried out on the site in a way that prevents or minimises adverse effects on the use of surrounding marine environment and allows for effective management of the environmental impacts of the activity.
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6.4 Assessment Method
6.4.1 Marine Development Footprint
To accurately assess the potential impacts to the marine environment the proposed marine development footprint and activities were identified. Key elements of the Project in regards to the marine environment and potential impacts include the following:
. BLF;
. RoRo facility;
. Marine operations and barge route;
. Barge moorings; and
. Offshore transhipment area.
The aforementioned Project marine components are summarised below and in further detail in Chapter 2 – Description of the Project.
Dredging or bed-levelling is not proposed to access the Skardon River. No changes to bed morphology is expected from the proposed operations.
6.4.1.1 Barge Loading Facility
The proposed BLF will be located at the river bend at the downstream extent of the Mine Lease Area (MLA) in the deep water to achieve an alongside depth of 4.5 m at Lowest Astronomical Tide (LAT) (Figure 6-1). The BLF consists of the following components:
. A causeway of approximately 100 m in length, with a 6 m wide crest will be constructed along the alignment of the outloading conveyor;
. A piled jetty consisting of a 6m wide concrete deck, supported on steel girders, which are in turn supported by steel headstocks, each on two driven steel tubular piles. The piled headstocks are at 12 m centres along the alignment of the jetty;
. A loading head deck to support the barge loader, to provide a small working deck for maintenance access to the barge loader, to provide access to berthed vessels and to allow turn- around space for vehicles; and
. Four berthing dolphins are provided on either side of the loading head, to provide vessel berthing points over an extended quay line (Figure 6-1).
6.4.1.2 Roll on/Roll off Facility
The RoRo facility will be located adjacent to the MIA on the Skardon River. The facility includes a concrete barge ramp designed for logistic support barges, to facilitate the unloading of cargo. The ramp will be located at approximately mean sea level to allow access at high tide by barges with a maximum draft < 2.0 m. To limit mangrove removal the ramp will be located at the narrowest section of mangroves that adjoins the MIA.
6-4 Bauxite Hills Project Marine Ecology
The barge ramp consists of precast concrete slab panels placed over rock fill. The slope of the ramp is at 1:7, which is the preferred ramp slope for the operation of logistic support barges. Ramp top level will be set at Highest Astronomical Tide level, to place it above normal high tide events.
6.4.1.3 Barge Operations
Bauxite transportation will be via shallow draft barge through the Skardon River and will occur 24 hours per day during the eight to nine month operational period (the Project will not operate in the wet season). Barges with a capacity of approximately 3,000 t will be used in year one to deliver 1 Mtpa and from year two onwards barges with a capacity of approximately 7,000 twill be used to deliver up to 5 Mtpa to awaiting Ocean Going Vessels (OGVs). Barge loading will be carried out using a stationary conveyor transferring the ore from the product stockpiles to the barge.
Each barge will be loaded taking into consideration potential navigational limitations at the time of loading. Where loading occurs during periods of low water, barges will be light-loaded to retain sufficient under keel depth. Conversely, during periods of high water, barges will be more fully loaded, but still within design specification of the barge, to cater for greater under keel depths. It is expected that transit at the river mouth will be limited for approximately seven hours a day during low tide.
Shallow draft tugboats will standby with the barges during loading. Barges will then be delivered to the transhipment location where they will be discharged to the awaiting carrier. Predicted barge movements are detailed in Chapter 2 – Description of the Project and Appendix I – Shipping Technical Report.
6.4.1.4 Barge Moorings
When not in use the barges will be moored in the Skardon River clear of other river traffic. The base case will include four sets of pile type moorings (consisting of two piles) for each tug and barge set and two sets of piles for each of the two floating cranes (Figure 6-1). Piles are planned to be removed at the end of mine life. The moorings will be designed to withstand cyclones (cyclone rated) and tugs and barges will be secured to these moorings during the wet season.
A separate single “day mooring” will be established in offshore water between the mouth of the Skardon River and the OGV loading area. The structure of the moorings will be like other standard moorings, comprising a single weight with a buoy attached. This mooring will not be cyclone rated but will be of sufficient design to be able to withstand 30 knots and 2 m seas.
6.4.1.5 Offshore Transhipment Area
The options for the OGV anchorage area has been assessed to ensure it is sufficiently far away from any sensitive marine habitats (reef assemblages) to avoid any potential impacts. The current location is to the north of the reef assemblages and to the north west of the Skardon River mouth. The indicative OGV anchorage area, relevant to the different OGV sizes, is shown in Figure 6-2. Whilst this proposed anchorage area requires a longer and less direct transit than some other options that had been proposed, Metro Mining decided this option provided the lowest risk of environmental impact.
Bauxite will be shipped to overseas markets via a combination of Supramax, Ultramax, Panamax and Mini Capesize Class Vessels. Geared Supramax and Ultramax class OGVs will be used during year one and until such time that the floating crane system is established. Once the floating crane is operational all four classes of OGV will be utilised. Dependent on the class of OGV, loading will take approximately four to six days, requiring between 15 to 20 loaded barges to complete each cargo.
6-5 SCALE 1:
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8700000 8690000 Bauxite Hills Project Marine Ecology
6.4.2 Desktop Assessment
A desktop assessment was carried out to identify potential matters of ecological significance including marine species and communities, as well as other ecological features occurring within the vicinity of the Project area. The desktop review was used to obtain background information relating to the potential presence and distribution of species particularly those listed under the NC Act and EPBC Act. Desktop studies involved database searches and review of:
. Commonwealth EPBC Act Protected Matters Search Tool (Department of the Environment (DotE)) - as a number of EPBC-listed species have changed status over the course of this assessment the most recent search available has been used as a reference point for assessment of marine ecology values;
. Queensland wetland mapping as sourced from EHP’s Wetland Info database;
. A number of reports with direct relevance to the Project area include:
• Port of Skardon River: Marine habitat resources survey April/May 2002 (Roeloffs et al., Marine Ecology Group, QFS, Northern Fisheries Centre, Cairns, 2002)
• Port of Skardon River: Marine Habitat Resources Survey, September 2003 (Roeloffs et al. Marine Ecology Group, QFS, Northern Fisheries Centre, Cairns, 2004)
• Port of Skardon River: Marine Habitat Resources Survey, December 2006 (Rasheed et al., Marine Ecology Group, QFS, Northern Fisheries Centre, Cairns, 2007)
• Benthic marine habitat of the Skardon River mouth, May 2010 (Chartrand and Thomas, Marine Ecology Group, QFS, Northern Fisheries Centre, Cairns, 2010)
. Reporting with regard to marine fauna for nearby Environmental Impact Statements for the Skardon River Bauxite Project (SRBP) Marine Ecological Survey (November 2014 (RPS, 2014)) and the Amrun (South of Embley) Project (Weipa area).
The extensive marine ecology surveys and reporting undertaken as part of the baseline work for the previously proposed Pisolite Hills Project has been used as the predominant marine ecology document for the Project. This work was focussed on Port Musgrave, approximately 25 km south of the Skardon River. As Port Musgrave is recognised as having a significantly larger, protected estuarine area than Skardon River, has been mapped with relatively large seagrass meadows and is fed from the large perennial rivers of both the Ducie and the Wenlock systems, the findings in the Port Musgrave work are considered to represent a potentially wider range of species niches than would be available in the Skardon River. The Project has adopted the conservative approach of assuming any species found in the Port Musgrave study could also occur in the Skardon River, even where conditions may be less optimal than in Port Musgrave.
6.4.3 Field Surveys
Field surveys of Skardon River for benthic marine habitat and seagrass extent were undertaken by PaCE in 2014 and 2015. The surveys were conducted to better understand benthic habitats from upstream of the proposed barge developments to the Skardon River entrance. Offshore habitats, within three proposed transhipment locations, and several bathymetric ‘high spots’ were also surveyed.
PaCE (2014) surveyed the benthic habitats adjacent to the three BLF locations originally proposed by Metro Mining during the end of the dry season (November). A total of 48 locations were surveyed
6-8 Bauxite Hills Project Marine Ecology
using benthic video techniques. The video surveys covered a distance of approximately 20-30 m of seabed over a two minute period at each location.
In addition to the survey undertaken around the proposed BLF options for seagrass, data was also collected for other benthic habitats. The survey included 116 locations to extend the understanding of benthic habitats downstream to the Skardon River entrance and offshore at the proposed transhipment locations. Sites where distributed randomly within the river system or targeted given available bathymetric survey information (i.e. rocky reef). Video data was analysed and biota recorded within key classes including, total live cover, macroalgae, macroinvertebrates, coral and bare substrate cover.
Water quality and sediment samples were also collected as part of PaCE’s surveys and these are discussed in Chapter 9 – Water Quality and Chapter 19 – Coastal Environment. 6.5 Existing Environmental Values
The Gulf of Carpentaria is a large and relatively shallow body of water which is enclosed on three sides by the Australian mainland and bounded on the north by the Arafura Sea. The Gulf of Carpentaria can be subject to seasonal fluctuations in sea level (up to 0.5 m) as a result of trade winds (e.g. during the monsoon) and forcing from the Arafura Sea (Wolanski, 1993). These seasonal sea level fluctuations can result in large areas being inundated by tides in the summer months (during the monsoon). As a result these areas cannot support mangrove or freshwater vegetation and therefore form salt flats.
Ryan et al., (2003) describes Skardon River as a tidal creek given the low freshwater input, low- gradient and seaward-sloping coastal flats. These systems are primarily influenced by tidal currents and as a result comprise straight, sinuous or dendritic tidal channels that taper and shoal to landward. The mudflats which surround the creeks tend to be high relative to the tidal planes, with seawater being mainly confined to the tidal channels except during high tide on spring tides. Tidal creeks are usually highly turbid due to the strong tidal currents generated by the macro-tidal ranges allowing fine sediments to remain in suspension during spring tides. The tidal action results in the transport of sediment into the estuary, where the sheltered conditions eventually allow the coarser sediment fractions to settle. The currents within the creek will be influenced by the channel depth and orientation along with the difference in tidal range through the creek.
The configuration of the Skardon River ranges from a relatively narrow 300 m width at the river entrance, quickly expanding to approximately 1 km upstream. The river starts to narrow about 3 km upstream and ranges in widths of between 500 to 600 m to the downstream point where the river branches into two arms. The site of the BLF and RoRo are located approximately 10 km upstream of the mouth of the river and approximately 2 km upstream of where the river branches into two arms. The river is approximately 350 m at this point. Further upstream the river the river continues to narrow and turns from being tidal into narrow ephemeral drains.
Due to the narrow entrance of the Skardon River combined with the complex and relatively shallow bathymetry of the ebb tidal delta and the offshore channel, swell waves are not expected to propagate inside the Skardon River. The area upstream of the entrance will therefore only be influenced by locally generated wind waves.
The dominant wind direction does not align with the estuaries main axis. This feature combined with the river configuration causes the locally generated wind waves to be small and have a short wave period. Based on this, along with the dominance of tidal currents within the river, wind generated waves in the estuary are not considered to be a significant process.
6-9 Bauxite Hills Project Marine Ecology
The bathymetry of the main channel in Skardon River along with areas of indicative bed forms are shown in Figure 6-3 and the results of the 2015 bathymetry survey are included in Appendix B3. The highest tidal current speeds in an estuary tend to occur close to the entrance. Due to the configuration of the Skardon River, the peak speeds are expected to occur at the constriction of the entrance where a flatbed occurs. The flatbed indicates that the flow velocity exceeds the speed at which ripples and mega ripples form, with peak current speeds potentially exceeding 1 m/s. Offshore of the entrance, mega ripples and sand waves occur in the main channel where current speeds remain high due to the constrained channel focusing the flow.
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8696000 608000 610000 612000 614000 616000 618000 8696000 RDetails Date ©COPYRIGHT CDM SMITH DESIGNER CLIENT Figure 6- This drawing is confidential and shall only be used DISCLAIMER 1 Draft 16/07/15 for the purpose of this project. CDM Smith has endeavoured to ensure accuracy and completeness of the data. CDM Smith assumes Bathymetry of Skardon River (September 2009) 2 Updated Pit Extents 22/03/16 / no legal liability or responsibility for any decisions DESIGNED MD CHECKED - with bed features noted - - 05250 001,000 or actions resulting from the information contained within this map. - DRAWN MD CHECKED - Metres - DATA SOURCE Scale @ A3 - 1:30,000 - - APPROVED - DATE 22/03/16 Acoustic Imaging; MEC Mining; GCS GDA 1994 MGA Zone 54 QLD Government Open Source Data; - - Notes: Australian Hydrological Geospatial Fabric (Geofabric) PRODUCT SUITE V2.1.1 - - DRG Ref: BES150115-027-R1_BATHYM_SR F:\1_PROJECTS\BES150115_Bauxite_Hill\GIS\DATA\MXD\FINAL\ERA\BES150115-027-R1_BATHYM_SR.mxd Bauxite Hills Project Marine Ecology
6.5.1 Coastal Habitats
The Skardon River and adjacent inshore and offshore areas encompass several marine habitats, including; saltmarsh, mangroves, seagrass, rocky reef, oyster reef, coral reef and broad areas of intertidal and subtidal soft substrates that are either bare or variably colonized by macroinvertebrates and macroalgal communities. This section describes the coastal (terrestrial) habitats within the Project area. The following coastal habitats are associated with the Project:
. Saltmarsh;
. Mangroves; and
. Wetlands.
The DNRM Regional Ecosystems (RE) currently mapped within the Project area is presented within Table 6-2 and Figure 6-4.
Table 6-1 Regional ecosystems within the Skardon River - marine vegetation Status* RE Code Community Description EPBC Act VMA 3.1.1a Long-styled Stilt Mangrove (Rhizophora stylosa) +/- N/A LC Large-leaved Orange Mangrove (Bruguiera gymnorhiza) closed forest as outer mangroves 3.1.3 Yellow Mangrove +/- Northern Grey Mangrove low N/A LC closed forest on intertidal areas 3.1.6 Sparse herb land or bare saltpans associated with salt N/A LC plains and saline flats, including saltmarsh *Status: Queensland Vegetation Management Act (VMA): E = Endangered, OC = Of Concern, LC = Least Concern
6.5.1.1 Saltmarsh
Defined clearly from aerial imagery, saltpan and fringing saltmarsh habitats are present throughout the Skardon River system. These habitats exist as a fringe between the dominant open woodland and Melaleuca vegetation, and the mangrove habitats (see Plate 6-1) and are characterised by periodic inundation leading to hypersaline soils, becoming bare saltpans in some instances. Plants displaying adaptations to these harsh conditions include samphires (Halosarcia sp.), and several marine grasses (Sporobolus sp., Fimbristylus sp. Tecticornia sp.). The mangroves bordering these habitats, at their landward extents, typically include Excoecaria sp. and Avicennia sp.
Where the interaction of freshwater allows a reduction in soil salinity, and slight elevations preclude saline inundation, sedges and grassland swamps may also develop (Perry, 1995). Species recorded from these habitats include the sedge Eleocharis sp., Marine Couch (Xerochloa sp.) and Fimbristylus sp., and emergent trees and shrubs including Melaleuca sp. and Grevillea sp. (Perry, 1995).
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Plate 6-1: Typical saltmarsh (foreground) and mangroves (rear)
The location of the proposed BLF does not cross mapped saltmarsh habitats or saltpans. A listing of saltmarsh species encountered during surveys by Roleofs et al. (2003) and PaCE (2014 and 2015) is presented within Appendix B3 – Marine Ecology and Coastal Processes. The extent of saltpan communities in the study area is presented in Figure 6-4.
6.5.1.2 Mangroves
Mangrove communities of Cape York are considered one of the world’s most species rich, supporting over 30 mangrove species that are unique to the region. Mangroves are also known to support more than 75% of all Australia’s commercially and recreationally important fish and crustacean species during some phase of their lifecycle (Abrahams et al., 1995; Duke, 2006; Quinn, 1992). They provide a structurally complex habitat that can provide protection for juveniles and a source of carbon that may be exported by the tide to other areas and food webs in the region (Manson et al., 2005; Meynecke et al., 2008).
A community of fringing mangrove habitat exists along the shores of the Skardon River, extending from just inside the mouth to the upper estuary/freshwater interface (see Plate 6-2). Roelofs et al. (2002) have surveyed the mangrove communities along the Skardon River. A list of mangrove species encountered is presented within Table 6-2. The extent of mangrove communities in the study area is presented in Figure 6-4.
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Plate 6-2: Mangrove community in Project area
The Long-styled Stilt Mangrove is the dominant mangrove community fringing the waterways of the Skardon River. Grey Mangrove and Yellow Mangrove communities are commonly established behind the mangrove fringe, nearest the saltpan/saltmarsh. Grey Mangrove species are also present along the leading edge of the mangrove community adjacent to low gradient mudflats. Patches of mangrove apple were also identified by Roelofs et al. (2002) being previously mapped as gaps in the mangrove fringe by Danaher (1995). PaCE noted the presence of mangrove apple within the vicinity of the proposed barge loading footprint.
The mangrove vegetation of the Skardon River is in good condition, with little evidence of disturbance and a well distributed range of life stages from juveniles to flowering adults. Historical clearing of a thin mangrove fringe has been undertaken at the nearby existing Port of Skardon barge ramp. Isolated minor impacts from feral pigs and cattle were also observed over the saltpan, saltmarsh, and landward fringe of the mangrove community across the study area. The mangroves identified from the Skardon River reflect the findings of previous surveys (Danaher, 1995; Perry 1995) and are typical of Cape York Peninsula (Bunt et al., 1982).
6.5.1.3 Observed Vegetation
The vegetation species that have been observed in mangrove, samphire, seagrass and sedgeland communities in the area during previous studies are identified in Table 6-2.
Table 6-2 Vegetation of the Skardon River (adapted from Roelofs et al., 2002) Species Common Name PaCE (2014- Roelofs et Literature Review 2015) al. (2002) Mangroves Rhizophora stylosa Red Mangrove Danaher 1995; Perry 1995 Rhizophora apiculata Tall-stilted Mangrove Danaher 1995; Perry 1995 Ceriops tagal Yellow Mangrove Danaher 1995; Perry 1995 Bruguieria gymnorhiza Large-leaved Orange Danaher 1995; Perry 1995 Mangrove Bruguieria parviflora Small-leaved Orange Danaher 1995; Perry 1995 mangrove
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Species Common Name PaCE (2014- Roelofs et Literature Review 2015) al. (2002) Sonneratia sp. Mangrove apple Danaher 1995; Perry 1995 Avicennia marina Grey mangrove Danaher 1995; Perry 1995 Xylocarpus granatum Cannonball mangrove Danaher 1995; Perry 1995 Xylocarpus moluccensis Cedar mangrove Danaher 1995; Perry 1995 Excoecaria agallocha Blind-your-eye Danaher 1995; Perry 1995 mangrove Osbornia octodonta Myrtle Mangrove Danaher 1995; Perry 1995 Aegialitis annulata Club Mangrove Danaher 1995; Perry 1995 Lumnitzera racemosa Black Mangrove Danaher 1995; Perry 1995 Nypa fruticans Mangrove Palm Danaher 1995; Perry 1995 Heritiera littoralis Looking-glass Danaher 1995; Perry 1995 Mangrove Acrostichum speciosum Mangrove Fern Danaher 1995; Perry 1995 Aegiceras corniculatum River Mangrove Danaher 1995; Perry 1995 Hibiscus tiliaceus Native Hibiscus Danaher 1995; Perry 1995 Samphires Halosarcia spp. Pigface Cited in Perry 1995 Fimbristylis spp. Danaher 1995 Tecticornia australasica Danaher 1995 Suaeda arbusculoides Samphire Bush Danaher 1995 Sarcocornia Tree Samphire Danaher 1995 quinqueflora Marine Grasses Sporobolus virginicus Saltwater Couch Danaher 1995 Sphaeranthus indicus Cited in Perry 1995 Xerochloa sp. Cited in Perry 1995 Sedgeland Eleocharis sp. Danaher 1995; Perry 1995
6.5.1.4 Intertidal Habitats
Intertidal habitats surrounding the entrance to the Skardon River are dominated by sand beaches, exposed to prevailing wind and waves from the Gulf of Carpentaria. As the shoreline progresses into the estuary and river system, silty sands and muds begin to dominate the intertidal substrate. This is accompanied by increasing mangrove habitat, declining sandy shores, ironstone banks and Casuarina dominated habitat. The distribution of intertidal mud and sandbanks at the entrance and inner estuary system is quite extensive. As the river progresses upstream the width of the primary waterway narrows. The edge of the banks become steeper, particularly on the outer bank curves, favoring the establishment of mangroves such as Rhizophora sp. Further upstream within the small tributaries, the channels may dry completely or almost completely at low tide. These intertidal habitats are predominately bare mud and silty/sand with the presence of some isolated patches of filamentous algae and oyster beds (Roleof et al., 2002; PaCE, 2015).
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6.5.1.5 Wetlands
The mangroves and adjacent saltmarsh/saltpans are considered to form part of the Skardon River – Cotterell River Aggregation (Figure 6-5). This wetland is listed under the Directory of Important Wetlands in Australia (DIWA). The criteria applied to reaching this listing included:
. It is a good example of a wetland type occurring within a biogeographic region in Australia;
. It is a wetland which is important as the habitat for animal taxa at a vulnerable stage in their life cycles, or provides a refuge when adverse conditions such as drought prevail; and
. The wetland supports native plant or animal taxa or communities which are considered endangered or vulnerable at the national level.
No Ramsar listed wetlands are mapped within or adjacent to the Project area.
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R Details Date ©COPYRIGHT CDM SMITH DESIGNER CLIENT This drawing is confidential and shall only be used DISCLAIMER Figure 6-5 1 For Information Purposes 16/07/15 for the purpose of this project. CDM Smith has endeavoured to ensure accuracy and completeness of the data. CDM Smith assumes Skardon River wetland classification 2 Updated Pit Extents 03/05/16 / no legal liability or responsibility for any decisions DESIGNED MD CHECKED - - - 0 500 1,000 2,000 or actions resulting from the information contained within this map. - DRAWN MD CHECKED - Metres - DATA SOURCE Scale @ A3 - 1:70,000 - - APPROVED - DATE 03/05/16 MEC Mining; GCS GDA 1994 MGA Zone 54 QLD Government Open Source Data; - - Notes: Australian Hydrological Geospatial Fabric (Geofabric) PRODUCT SUITE V2.1.1 - - DRG Ref: BES150115-003-R1_WETLANDS F:\1_PROJECTS\BES150115_Bauxite_Hill\GIS\DATA\MXD\FINAL\ERA\TER FW ECOL\BES150115-003-R1_WETLANDS.mxd Bauxite Hills Project Marine Ecology
6.5.2 Benthic Habitats
6.5.2.1 Seagrass
Several surveys for the distribution and abundance of seagrass and associated benthic habitats have been undertaken within the Skardon River since 1986 (Table 6-3). The distribution of seagrass habitats from the surveys within the Skardon River is presented within Figure 6-4.
Table 6-3 Benthic habitat surveys undertaken from the Skardon River (1986-2015) Study Year Location Coles et al. 1986 Entrance Roelofs et al. 2002 Whole river dry season Roelofs et al. 2003 Whole river wet season Rasheed et al. 2007 Whole river Chartrand and Thomas 2010 Entrance PaCE 2014 Metro Mining BLF PaCE 2015 Downstream of the BLF to the Skardon River entrance
Initial surveys by Coles et al. (1986) identified two isolated patches of seagrass near the Skardon River estuary entrance. Further baseline investigations were undertaken during 2002 (wet season) and 2003 (dry season) (Roelofs et al., 2003). Seagrasses were recorded within a tributary to the main river channel during both these events: Narrowleaf Seagrass (Halodule uninervis). This included three small meadows located within 500 m of the existing barge ramp at the then kaolin processing area. Subsequent surveys undertaken in 2006 adjacent to the barge ramp facility (Rasheed et al., 2007) extended the distribution of seagrass nearer to the existing BLF, adding another small meadow which fringed the mangrove banks upstream to the extent of the port limits. Distribution of Narrowleaf Seagrass was also extended, reporting a low density meadow adjacent to the BLF.
Rasheed et al. (2007) described that seagrass distribution during 2006 (approximately 9.1 ha) was double that of the previous surveys in 2003 (approximately 4.4 ha), and noted that variability in the distribution of these meadows is not unusual. Paddle Grass (Halophila sp.) is a colonising species that can rapidly form meadows in the right conditions (i.e. lower rainfall, and greater benthic irradiance) (Rasheed et al., 2006).
During 2010, a detailed survey encompassing the then proposed barge access area was undertaken through the river entrance (Chartrand and Thomas, 2010). A Narrowleaf Seagrass meadow recorded earlier by Coles et al. (1986) was identified during this survey covering an area of approximately 1 ha. Although a total of 230 seagrass habitat characterisation sites were surveyed within the river entrance and surrounds, no additional seagrass communities were identified (Figure 6-6) (Chartrand and Thomas, 2010). The majority of the survey locations within the entrance reported open substrate, sand, or sand and shell matter.
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Figure 6-6 Seagrass survey of the Skardon River entrance (Chartrand and Thomas, 2010)
During the 2014 surveys, nine small paddle grass meadows were located in thin (<5 to 10 m width) patchy bands adjacent to the mangrove banks upstream of the existing BLF (PaCE, 2014). These extended up to and immediately beyond the proposed BLF. Seagrass coverage within the identified meadows averaged 19.9% cover (ranging between 0.5 and 57.8 % cover).
Deeper locations, central to the channel, did not appear to provide suitable conditions for seagrass colonisation. This follows the findings of previous investigations in the area (Rasheed et al., 2007) where seagrasses occurred nearest to the river banks where light conditions remain favourable. The proposed jetty and conveyor structure for the Project’s BLF are located within a deeper area of the river to optimise operations, but also to avoid seagrass meadows as much as possible. Based on the most recent survey of seagrass coverage (PaCE, 2014) the Project does not require direct clearing of any seagrass, but may indirectly impact up to 0.4 ha of seagrass habitat.
6.5.2.2 Subtidal Habitats
The majority of subtidal benthic habitats within the Skardon River estuary are dominated by open bare substrates of silt, silty/sand, sand and rock (approximately 77%). Only a very limited live benthic cover has been recorded within the Skardon River. Of the live cover recorded, macroalgae was dominant (17%). Macroinvertebrates were greatest within rocky shoals and rubble fields which provide a stable substrate for colonisation. These habitats include a range of macroinvertebrates dominated by sponges and ascidians, and brown macroalgae. Several intertidal areas of oyster rock/reef have been identified adjacent to mangrove banks.
A detailed survey undertaken by Chartrand and Thomas (2010), confirmed an absence of benthic habitat within the ebb tide bar. This incorporated over 200 sampling locations (Figure 6-6) Substrates were described as bare sand.
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6.5.2.3 Offshore anchorage areas
Three proposed anchorage areas for OGVs were surveyed using video techniques and side scan sonar. Anchorage Option 1 was located in deeper water (15-16 m LAT) approximately 4-5 km north of anchorage Options 2 and 3 (12-13 m LAT) (see Figure 6-2 and B3 – Marine Ecology and Coastal Processes). Benthic habitats within the anchorage areas were surveyed by underwater video at five locations and side scan sonar. The benthic habitat within the surveyed area was dominated by bare coarse shell and sandy substrates (96%). A sparse cover (of sea whips, sponges, gorgonian fans, ascidians and hard corals (Turbinaria spp.) were identified within the survey area and these biota appear to have created a scattered low profile sponge, soft coral and minor hard coral reef (profile <0.5 m). This was observed from 2 of the 5 survey locations.
6.5.2.4 Offshore Reef Habitats
Two additional offshore locations were surveyed using underwater video and side scan transects. These were selected based on elevations mapped within the existing bathymetry charts for the study area. Both locations contained rock/reef substrate as identified from side scan sonar transects. The nearest of these locations to the Skardon River mouth (approximately 5 to 7 km southwest) presented a high cover of hard corals (37%), associated soft corals and benthic macroinvertebrates (6%). Biota was encrusting over an underlying rocky reef, interspersed by coarse sand patches, shell and soft corals, ascidians and other non-encrusting biota. The extent of the rocky reef habitat at this location was estimated by reviewing side scan sonar imagery. The complex extended over 600 m in length and 300 m in width resulting in approximately 18 ha of potential rocky reef habitat. The edges of the feature were not fully identified and there is potential for this habitat area to be greater than this estimate. While the Project activities will not operate within or near this feature (refer Figure 6-2), care will be taken to ensure that supply vessels and general shipping accessing the Project remain clear of this habitat.
The percentage of substrate cover associated with the Skardon River, the three anchorage options and the reef patch, described above, is provided in Table 6-4.
Table 6-4 Percentage cover from the Skardon River, anchorage options and a nearshore reef patch Area Average percentage cover (%) Bare substrate Live cover Macroalgae Hard Coral Macro invertebrates River 77.4 22.6 17.4 0.00 0.8 Anchorages (Total) 96.4 2.5 0.1 0.31 2.0 Option 1 95.3 4.7 0.2 1.00 3.3 Option 2 99.1 0.9 0.1 0.00 0.8 Option 3 97.6 2.4 0.0 0.00 2.4 Reef patch 55.5 44.5 0.9 37.00 6.6
To avoid the reef structures that were identified during the marine surveys discussed above, Metro Mining moved the proposed anchorages to avoid the structures. Additionally a 1 km buffer was applied around each of the identified structures. The new anchorage locations and buffer zones are shown at Figure 6-2. Further surveys will be undertaken of the new anchorage areas prior to the commencement of operations.
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6.5.3 Commonwealth Marine Area
Commonwealth waters commence from the three nautical mile limit (Figure 6-2). They extend seaward to the 200 nautical mile limit (in the case of the Gulf of Carpentaria, the entire gulf waters are included). The areas identified for transhipping and movement of bulk carriers servicing the Project will be undertaken in Commonwealth marine waters. The location of the transhipment operations is dominated by open sandy substrates, with minor live benthic cover (1 – 3%). Mining and port activities occur approximately 10 km east of the mouth of Skardon River and 18 km to the south east of the Commonwealth Marine Area.
6.5.3.1 Commonwealth Marine Reserve
The West Cape York Commonwealth Marine Reserve is located to the northwest of Skardon River. The Reserve covers an area of 16,000 km2 comprising national park, multiple use and special purpose zones (see Figure 6-7). The reserve was declared in 2012 and includes the following uses:
. Marine National Park Zone – IUCN Category II (7,957 km2);
. Multiple Use Zone – IUCN Category VI (5,871 km2); and
. Special Purpose Zone – IUCN Category VI (2,184 km2).
Figure 6-7 West Cape York Commonwealth Marine Reserve
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IUCN Category II - Marine National Park Zones
Marine National Park Zones are large natural or near natural areas set aside to protect large-scale ecological processes, along with the complement of species and ecosystems characteristic of the area, which also provide a foundation for environmentally and culturally compatible spiritual, scientific, educational, recreational and visitor opportunities.
The primary objective of Marine National Park Zone is to protect natural biodiversity along with its underlying ecological structure and supporting environmental processes, and to promote education and recreation. Other objectives include:
. To manage the area in order to perpetuate, in as natural a state as possible, representative examples of physiographic regions, biotic communities, genetic resources and unimpaired natural processes;
. To maintain viable and ecologically functional populations and assemblages of native species at densities sufficient to conserve ecosystem integrity and resilience in the long term;
. To contribute in particular to conservation of wide-ranging species, regional ecological processes and migration routes;
. To manage visitor use for inspirational, educational, cultural and recreational purposes at a level which will not cause significant biological or ecological degradation to the natural resources;
. To take into account the needs of indigenous people and local communities, including subsistence resource use, in so far as these will not adversely affect the primary management objective; and
. To contribute to local economies through tourism.
Marine National Park Reserves provide large-scale conservation opportunities where natural ecological processes can continue in perpetuity, allowing space for continuing evolution. They are seen as key stepping-stones for designing and developing large-scale biological corridors or other connectivity conservation initiatives required for those species (wide-ranging and/or migratory) that cannot be conserved entirely within a single protected area. Their key roles are therefore:
. Protecting larger-scale ecological processes that will be missed by smaller protected areas or in cultural landscapes;
. Protecting compatible ecosystem services;
. Protecting particular species and communities that require relatively large areas of undisturbed habitat;
. Providing a “pool” of such species to help populate sustain-ably-managed areas surrounding the protected area;
. To be integrated with surrounding land or water uses to contribute to large-scale conservation plans;
. To inform and excite visitors about the need for and potential of conservation programmes; and
. To support compatible economic development, mostly through recreation and tourism, that can contribute to local and national economies and in particular to local communities.
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IUCN Category VI - Multiple Use Zone and Special Purpose Zone
Multiple Use Zones are protected areas that conserve ecosystems and habitats, together with associated cultural values and traditional natural resource management systems. They are generally large, with most of the area in a natural condition, where a proportion is under sustainable natural resource management and where low-level non-industrial use of natural resources compatible with nature conservation is seen as one of the main aims of the area. The primary objective is to protect natural ecosystems and use natural resources sustainably, when conservation and sustainable use can be mutually beneficial. Other objectives are:
. To promote sustainable use of natural resources, considering ecological, economic and social dimensions;
. To promote social and economic benefits to local communities where relevant;
. To facilitate inter-generational security for local communities' livelihoods – therefore ensuring that such livelihoods are sustainable;
. To integrate other cultural approaches, belief systems and world-views within a range of social and economic approaches to nature conservation;
. To contribute to developing and/or maintaining a more balanced relationship between humans and the rest of nature;
. To contribute to sustainable development at national, regional and local level (in the last case mainly to local communities and/or indigenous peoples depending on the protected natural resources);
. To facilitate scientific research and environmental monitoring, mainly related to the conservation and sustainable use of natural resources;
. To collaborate in the delivery of benefits to people, mostly local communities, living in or near to the designated protected area; and
. To facilitate recreation and appropriate small-scale tourism.
The general approval for the West Cape York Commonwealth Marine Reserve provides for the following activities to continue while a management plan is prepared:
. Commercial fishing; . Non-commercial fishing; . Commercial tourism; . Mining operations; . Commercial vessel transit (being continuous passage of a vessel through an area by the shortest direct route without any other activity being carried on); . Aquaculture; . Commercial media activities; . Commercial image capture; and . Erecting structures, carrying out works and carrying on an excavation.
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6.5.3.2 Marine Bioregional Plan for the North Marine Region
The study area also forms part of the area encompassing the Marine Bioregional plan for the Northern Marine Region (Figure 6-8). This plan covers the Commonwealth marine area extending from west Cape York Peninsula to the Northern Territory–Western Australia border. The plan does not cover state or territory waters but, where relevant, does include information about inshore environments and the way they interact with species and habitats of the Commonwealth marine area.
The Commonwealth has prepared the Marine Bioregional Plan for the North Marine Region. The Plan area covers approximately 625,689 km2 of tropical waters in the Gulf of Carpentaria and Arafura and Timor seas, and abuts the coastal waters of Queensland and the Northern Territory. The key ecological features of relevance to the Project are the Gulf of Carpentaria coastal zone and the Gulf of Carpentaria basin (for bulk carrier vessel ship movements only).
The plan presents a summary of the analysis of pressures affecting conservation values in the region undertaken to inform the development of regional priorities. The marine bioregional plan identified 12 regional priorities comprising six conservation values and six pressures. The six conservation values are:
. Listed marine turtles;
. Listed inshore dolphins;
. Listed sawfishes and river sharks;
. Dugong;
. Listed sea snakes; and
. The Gulf of Carpentaria coastal zone.
The conservation values are all relevant to the Project, and the listed marine species known or likely to occur in the Project area are described in Section 6.5.4. The six pressures that are regional priorities are less relevant to the Project, as the Project:
. Will not increase pressure associated with marine debris, bycatch, extraction of living resources (illegal, unreported and unregulated fishing) or climate change;
. Will involve physical habitat modification in the form of port infrastructure construction, however this activity is minor, transient and not within Commonwealth marine waters, nor is it likely to result in impacts to Commonwealth marine waters; and
. May involve very minor modification of hydrological regimes from mining activities, although this is highly unlikely to impact Commonwealth marine waters (for further discussion on the hydrological regime of the Project area see Chapter 10 – Water Resources, Chapter 11 – Flooding and Regulation Structures and Appendix E2 – Surface Water Technical Report).
The marine bioregional plan identifies the six pressures of potential concern on ecosystem functioning and integrity on the Gulf of Carpentaria coastal zone are:
. Marine debris (e.g. derelict fishing nets, discarded plastic);
. Fishing bycatch;
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. Extraction of living resources (illegal, unreported and unregulated fishing);
. Physical habitat modification;
. Climate change (sea level rise, ocean acidification, changed temperature); and
. Changes in hydrological regimes.
The marine bioregional plan identifies that the pressures of potential concern on ecosystem functioning and integrity on the Gulf of Carpentaria basin are illegal, unreported and unregulated fishing, marine debris and climate change. Project shipping in the Gulf of Carpentaria basin will not contribute to these pressures.
In terms of the marine bioregional plan strategies to address regional priorities, the Project contributes to Strategy D, through the EIS process, by increasing collaboration with relevant industries to improve understanding of the impacts of anthropogenic disturbance and address the cumulative effects on the region’s key ecological features and protected species.
Figure 6-8 North Marine Region area 6.5.4 Conservation Significant Species
The EPBC Act Protected Matters Search Tool aims to include species which are likely to occur in a geographic region, based on known ranges and habitat preferences. Inclusion in the report does not necessarily mean that the animal or plant will occur at a specific location. Consideration of site specific information is important for augmenting the results of the protected matters search and verifying that an animal or plant does occur at a specific locality, or has a high likelihood of occurring based on habitat attributes. Additionally, site specific information may identify that a species of conservation significance not included in the EPBC Act Protected Matters search may occur or is highly likely to occur based on habitat attributes.
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The EPBC Act Protected Matters Search Tool for the Project area identified the following:
. 30 species listed as threatened, of which 15 may be considered marine species;
. 39 fauna species listed as Migratory, of which 22 are marine species;
. 62 species listed as marine species; and
. 11 whales and cetaceans.
The marine species that are known to occur or are likely to occur at or adjacent to the proposed Project location are listed in Table 6-5 (see also Appendix B3 – Marine Ecology and Coastal Processes). The listing status under the EPBC Act, the NC Act and the International Union for Conservation of Nature (IUCN) are included. Bird species that are listed as Migratory under the EPBC Act are treated in Chapter 5 – Terrestrial and Aquatic Ecology and Chapter 7 – Matters of National Significance.
Table 6-5 Conservation status listed species that are known to occur or likely to occur Species EPBC Act Status NC Act Status IUCN Status Marine Reptiles Flatback Turtle (Natator Vulnerable, migratory marine Vulnerable Not assessed depressus) species, listed marine species Loggerhead Turtle (Caretta Endangered, migratory marine Endangered Endangered caretta) species, listed marine species
Green Turtle (Chelonia mydas) Vulnerable, migratory marine Vulnerable Endangered species, listed marine species Olive Ridley Turtle Endangered, migratory marine Endangered Vulnerable (Lepidochelys olivacea) species, listed marine species
Hawksbill Turtle (Eretmochelys Vulnerable, migratory marine Vulnerable Endangered imbricata) species, listed marine species
Estuarine Crocodile (Crocodylus Migratory marine species, listed Vulnerable Least concern porosus) marine species
Sea snakes (18 species) Listed marine species Not listed Not assessed, least concern or data deficient Mammals Dugong (Dugong dugon) Migratory marine species, listed Vulnerable Vulnerable marine species Australian Hump-backed Migratory marine species, whales Vulnerable Near threatened Dolphin (Sousa sahulensis) and other cetaceans Australian snubfin dolphin Migratory marine species, whales Vulnerable Near threatened (Orcaella heinsohni) and other cetaceans Spotted Dolphin (Stenella Whales and other cetaceans Not listed Least concern attenuata) Bottlenose Dolphin (Tursiops Whales and other cetaceans Not listed Least concern truncatus s. st.) Fish and Sharks Narrow Sawfish (Anoxyprostis Migratory marine species Not listed Endangered cuspidata) Speartooth Shark (Glyphis Critically endangered Not listed Endangered glyphis) Coastal Manta Ray (Manta Migratory marine species Not listed Vulnerable alfredi)
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Species EPBC Act Status NC Act Status IUCN Status Dwarf Sawfish (Pristis clavata) Vulnerable Not listed Endangered Largetooth Sawfish (Pristis Vulnerable Not listed Critically pristis) endangered Green Sawfish (Pristis zijsron) Vulnerable Not listed Critically endangered Pipefishes (34 species) Listed marine species Not listed Not assessed, least concern or data deficient (*) The taxonomy of the Bottlenose Dolphin remains to be determined.
A number of marine fauna species identified in the EPBC Act Protected Matters search, were considered to not occur regularly (i.e. the study area may not be considered as within the species normal distribution or habitat requirements), or are highly unlikely to occur at or adjacent to the Project. Those species listed along with a brief justification as to why they were not considered is provided in Table 6-6. Further detail on marine species is provided in Chapter 7 – Matters of National Significance and the Marine Ecology and Coastal Processes Technical Report (Appendix B3).
Table 6-6 Listed marine species considered unlikely to occur Species EPBC Act Status NC Act Likelihood of Occurrence Justification Status Marine Reptiles Leatherback Endangered, Endangered No major nesting has been recorded in Australia, Turtle migratory marine although scattered isolated nesting occurs in southern (Dermochelys species, listed marine Queensland and the Northern Territory. Some nesting coriacea) species has occurred in northern NSW near Ballina. However, no nesting is known to have occurred in Queensland or New South Wales (NSW) since 1996. The species is most commonly reported from coastal waters in central eastern Australia (from the Sunshine Coast in southern Queensland to central NSW); south-east Australia (from Tasmania, Victoria and eastern South Australia) and in south-western Western Australia. Based on this information Leatherback Turtles are highly unlikely to nest on western Cape York beaches or use the Gulf of Carpentaria as an important feeding area. It should be noted that the measures in place to mitigate the risk to the other five turtle species will also benefit the Leatherback Turtle if new information demonstrated regular use of the relevant area by the species. Freshwater Listed marine species Not listed The species is generally found in freshwater Crocodile environments rather than marine, hence its common (Crocodylus name. Although it has a range across much of northern johnstoni) Australia it is not found in northern Cape York Peninsula including the region of the Project area. The species relies on the presence of permanent, large waterholes stocked with fish as prey and which do not occur in the wider area. Mammals Bryde’s Whale Migratory marine Not listed There are two forms of Bryde’s Whale: the coastal from (Balaenoptera species, whales and of Bryde's Whale appears to be limited to the 200 m edeni) other cetaceans depth isobar, moving along the coast in response to availability of suitable prey. The offshore form is found in deeper water (500 m to 1,000 m). No specific feeding
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Species EPBC Act Status NC Act Likelihood of Occurrence Justification Status or breeding grounds have been discovered off Australia. While Bryde’s Whale may infrequently occur in the Gulf of Carpentaria, the region can be considered outside their normal distribution. Blue Whale Endangered, Not listed The only known areas of significance to Blue Whales in (Balaenoptera Migratory marine Australian waters are feeding areas around the musculus) species, whales and southern continental shelf, notably the Perth Canyon, cetaceans in Western Australia, and the Bonney Upwelling and adjacent upwelling areas of South Australia and Victoria. Blue whales are not known to regularly migrate through, aggregate, feed or breed in the Gulf of Carpentaria and as such the area is considered to be outside of their normal range. Humpback Whale Vulnerable, Migratory Vulnerable The feeding, migratory and calving areas for the (Megaptera marine species, eastern Australian and Western Australian populations novaeangliae) whales and other of Humpback Whales are known. The Great Barrier cetaceans Reef complex and the Kimberley Region are important breeding and calving grounds for Humpback Whales. Hervey Bay and the Whitsundays appear to be important resting grounds for mothers and calves of the east coast population on their southward migration. Humpback Whales are not known to regularly migrate through, aggregate, feed or breed in the Gulf of Carpentaria and as such the area is considered to be outside of their normal range. Killer Whale Migratory marine Not listed A single individual has been observed near Weipa in (Orcinus orca) species, whales and August 2014 (Cairns Post, 2014). However, Killer other cetaceans Whales are more common in cold, deep waters, or inshore shelf waters near seal and sea lion colonies. As such the Gulf of Carpentaria and hence the study area can be considered to be outside its normal range. Common Dolphin Whales and other Not listed Common Dolphins are found in offshore oceanic waters (Delphinus cetaceans and are rarely seen in northern Australian waters. delphis) Common Dolphins appear to occur in two main locations around Australia, with one cluster in the southern south-eastern Indian Ocean and another in the Tasman Sea. As the species is found in offshore oceanic waters, the Gulf of Carpentaria can be considered to be outside its natural range. Risso’s Dolphin Whales and other Not listed Risso’s Dolphin has a marked preference for deep (Grampus griseus) cetaceans oceanic water. They occur mainly on steep sections of the upper continental slope, usually in waters deeper than 1000 m, in tropical and warm temperate latitudes. As the species is found in deep offshore oceanic waters, the Gulf of Carpentaria can be considered to be outside its natural range. Water Mouse Vulnerable Vulnerable For more information this species is referred to in (Xeromys Chapter 5 – Terrestrial and Aquatic Ecology myoides) Fish and Sharks Great White Vulnerable, Migratory Not listed The northern-most Queensland record is Mackay. Shark marine species Areas where observations are more frequent include (Carcharodon waters in and around some fur seal and sea lion carcharias) colonies such as the Neptune Islands (South Australia); areas of the Great Australian Bight as well as the
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Species EPBC Act Status NC Act Likelihood of Occurrence Justification Status Recherche Archipelago and the islands off the lower west coast of Western Australia. Juveniles appear to aggregate seasonally in certain key areas including the 90 Mile Beach area of eastern Victoria and the coastal region between Newcastle and Forster in NSW. Therefore, Great White Sharks are not known to regularly migrate through, aggregate, feed or breed in the Gulf of Carpentaria and as such the area is considered to be outside of their normal range. Whale Shark Vulnerable, Migratory Not listed Ningaloo Reef, off the Western Australian coast, is the (Rhincodon typus) marine species main known aggregation site of Whale Sharks in Australian waters. The species is generally found in areas of upwelling and at times when plankton abundance is very high (e.g. mass coral spawning event. Whale sharks are known to regularly migrate through, aggregate, feed or breed in the Gulf of Carpentaria and as such the area is considered to be outside of their normal range. Giant Manta Ray Migratory marine Not listed The Giant Manta Ray lives mostly in the open ocean, (Manta birostris) species traveling with the currents and migrating to areas where upwellings of nutrient-rich water increase prey concentrations. As such the Gulf of Carpentaria can be considered to be outside its natural range.
6.5.4.1 Marine Reptiles
Marine Turtles
Marine turtles nest on beaches throughout the western Cape York region; however, the Project will not impact upon turtle nesting habitat. The BLF and RoRo facilities locations are situated within a mangrove fringed estuary environment within the Skardon River, and are not suitable for any marine turtle nesting. Suitable nesting habitat is situated at the mouth of the Skardon River approximately 12 km downstream. Coastal beaches in the Mapoon and Skardon area provide suitable and regionally important turtle nesting habitat, with beaches north and south of the Skardon River entrance demonstrating nesting activity (RPS, 2014; Dr Riku Koskela pers. comm.). The following provides a brief summary of each species. For more detail refer to Appendix B3 – Marine Ecology and Coastal Processes.
Flatback Turtles are the most common nesting species in the proposed development area and the species nests only in Australia. Flatback Turtles in the region nest all year round, although peak nesting occurs from May through to September. Along the part of Western Cape York that has been surveyed, the beach between Port Musgrave and the Skardon River has the greatest prevalence of nesting for this species (Table 6-7). The most significant rookery in the Gulf of Carpentaria is Crab Island which is approximately 27 km south-west of Bamaga, and 75km north of the Project site (Limpus et al., 1983). Other significant rookeries in the Gulf of Carpentaria include the Wellesley and Sir Edward Pellew Islands (Limpus, 1995). In the north-western Torres Strait significant rookeries occur at Deliverance Island, Kerr Islet and Turu Cay (Limpus et al., 1989) (over 100 km from the Project site).
Within the Marine bioregional plan for the Northern Marine Region these areas have been identified as ‘biologically important areas’ (BIAs). The Plan describes implementation of an 80 km buffer
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around these locations for management consideration (DSEWPaC, 2012). The nearest BIA for Flatback Turtles includes Crab Island located approximately 85 km to the north of the Project site.
It is highly likely that Australia has the largest remaining breeding population of Olive Ridley Turtles in the southeast Asia–western Pacific region (Limpus, 2008a). Low density nesting occurs along the northwestern coast of Cape York Peninsula between Weipa and Bamaga (Limpus et al., 1983). Olive Ridley Turtle populations on western Cape York are at significant risk from the foraging activities of feral pigs (Whytlaw et al., 2013). Olive Ridley Turtles nest year round, although most nesting occurs during the dry season, from April to November. Low-density nesting occurs along the north western coast of Cape York Peninsula between Weipa and Bamaga (Limpus et al., 1983).
Hawksbill Turtles are generally associated with reef habitats. They feed principally on various species of sponge, but they may also feed on algae, soft corals and macro-zooplankton such as jellyfish and comb-jellies (e.g. Meylan 1988; Berube, 2010). Hawksbill Turtles are known to nest along western Cape York beaches, although the high density nesting locations are in Torres Strait (Long (Sassie) Island, Hawkesbury Island and Dayman Island) and islands in the northern Great Barrier Reef (e.g. Boydong Island and Milman Island) (Limpus, 2009). Nearshore coral reef habitats may provide feeding grounds. DSEWPaC (2012) identifies a BIA surrounding the mainland coast of Western Cape York Peninsula north of the Cotterell River. The Cotterell River is located approximately 40 km north of the Skardon River.
The important nesting locations (BIAs) for Green Turtle in the Gulf of Carpentaria are the Wellsley Islands, eastern Arnhem Land, Groote Eylandt and the Sir Edward Pellew Islands (Limpus 2008b). Western Cape York is not an important nesting location. Adult green turtles eat mainly seagrass and algae, although they will occasionally eat other items such as jellyfish and sponges (Read and Limpus, 2002; Arthur et al., 2007). Green Turtle is unlikely to be found near the Project area as no extensive beds of seagrass occur at, or adjacent to the proposed BLF location. Paddle Grass may be found as thin meadows of low density fringing the adjacent mangrove communities within the immediate subtidal zone. Algae and other macrophytes are also present. The biomass of seagrass and algae is unlikely to be suitable to support green turtles, even for a short period of time.
In Australia, the Loggerhead Turtle occurs in the waters of coral and rocky reefs, seagrass beds and muddy bays throughout eastern, northern and western Australia (Limpus et al. 1992). While nesting is concentrated in southern Queensland and from Shark Bay to the North West Cape in Western Australia, foraging areas are more widely distributed. The beaches adjacent to the proposed Project area are not important nesting locations for Loggerhead Turtles (and this applies to the whole of the western Cape York coast), although the waters are used for feeding.
Table 6-7 Number of turtle nesting tracks at four beach regions along western Cape York (modified from Bell, 2004) Location Beach distance surveyed (km) Turtle nesting tracks Archer River to False Pera Head 35 Flatback Turtle - 35 False Pera Head to Boyds Bay 38 Flatback Turtle – 41 Olive Ridley/Hawksbill Turtle - 2 Pennyfather River to Port Musgrave 39 Flatback Turtle – 60 Olive Ridley/Hawksbill Turtle - 1 Port Musgrave to Skardon River 35 Flatback Turtle - 95
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Estuarine Crocodiles
Estuarine Crocodile was recorded from the area during surveys for the SRBP (RPS, 2015). It is widespread throughout northern Australia and its range includes all of the Gulf of Carpentaria and the Queensland east coast south to the latitude of approximately Gladstone. The Port Musgrave area, and in particular, the Wenlock River, is recognised as containing significant habitat for the estuarine crocodiles with one of the largest breeding populations in Queensland (Abrahams et al., 1995; Read et al., 2004; EHP, 2013). The Draft Management Program for Crocodylus porosus in Queensland 2007-2017 (DERM, 2007) has highlighted Port Musgrave and north-western Cape York Peninsula as two of five areas recognised as a ‘principal geographic area’ where conservation efforts should be concentrated.
Their habitat includes marine habitats such as mangroves, but they also commonly occur in freshwater habitats such as rivers, lakes and swamps. Crocodiles have wide and varied diets which differ between habitats. Prey size increases with the size of the crocodile, with the diet of juveniles consisting of smaller prey such as insects, crustaceans and occasionally small mammals such as rats. Larger crocodiles feed on fish, crabs, turtles, birds and mammals including large prey items such as wallabies, pigs, water buffalo, cattle and horses.
Sea Snakes
The sea snake fauna has been assessed in detail in the Weipa area, and the dominant sea snake species is the Spine-bellied Sea Snake (Lapemis hardwicki) comprising approximately 90% of the sea snake fauna (Redfield et al., 1978). Other species recorded in the Weipa area include:
. Peron’s Sea Snake (Acalyptophis peronii);
. Reef Shallows Sea Snake (Aipysurus duboisii);
. Olive Sea Snake (Aipysurus laevis);
. Stokes’ Sea Snake (Astrotia stokesii);
. Common Sea Snake (Enhydrina schistosa);
. Elegant Sea Snake (Hydrophis elegans); and
. Reef Sea Snake (Hydrophis ornatus).
The aforementioned species have been recorded from multiple locations elsewhere in the Gulf of Carpentaria (Redfield et al., 1978). There are no specific studies that have examined the sea snake fauna specifically at the sites of the proposed development, however previous studies on marine ecology for the Skardon River have not noted any opportunistic sightings.
6.5.4.2 Marine Mammals
Dugong
Dugong are abundant at many locations in the Gulf of Carpentaria and are usually associated with seagrass beds. A major proportion of Dugong in the Gulf of Carpentaria occur in the region of the Wellesley Islands, the Sir Edward Pellew Group, and Blue Mud Bay (Saalfield and Marsh, 2004). Of the estimated 27,602 (± 3,110) Dugong in the Gulf of Carpentaria, only 15% occurred in the waters of the Queensland coast, reflecting the much greater area of seagrass along the Northern Territory coast (Saalfield and Marsh, 2004).
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Dugong are known to occur in low densities in Port Musgrave (Saalfield and Marsh, 2004) and are closely associated with the areas of seagrass beds in the area. Incidental observations while undertaking seagrass mapping identified the presence of dugong feeding trails in the seagrass beds which is further evidence of Dugong foraging in Port Musgrave (WorleyParson, 2010). Seagrass surveys have been undertaken within the Skardon River since the late 1980s. Over this period a single sighting for dugong has been recorded upstream within the Skardon River adjacent to the now decommissioned kaolin facility and barge ramp (Roelofs et al., 2003).
While some seagrass species preferred by Dugong occur is small patches within the Skardon River and even adjacent to the Port area, it is unlikely to constitute a sufficient biomass to sustain a population of Dugong. The Project is not at or adjacent to seagrass habitat that constitutes important dugong habitat. The main feeding locations for dugong in the Gulf of Carpentaria are known and are remote from the Project location.
Whales and Dolphins
Of the cetacean species predicted to occur in the area only one species has been recorded in the Skardon River estuary and surround waters: Australian Snubfin Dolphin (Orcaella heinsohni) (Table 6-8). No whales or dolphins (cetaceans), that are listed by the state or Commonwealth as threatened species are likely to occur at or adjacent to the proposed Project location. All cetacean species are given specific protection under the EPBC Act as listed “whales and other cetaceans” and in a number of instances, migratory marine species. This assessment identified that five species of cetaceans are likely to occur at or adjacent to the Project location: Indo-Pacific Humpback Dolphin (Sousa sahulensis), Australian Snubfin Dolphin, Spotted Dolphin (Stenella frontalis), and Bottlenose Dolphin species (Tursiops sp.)
The preferred habitat of Australian Snubfin Dolphins can vary regionally but there is no information to describe habitat preference of the species in the Gulf of Carpentaria. In the Townsville area they prefer shallow waters (1 to 5 m) (Parra, 2006), whereas those in the Keppel Bay region (central Queensland coast) range from 2 to 15 m (Cagnazzi et al. 2013). Investigations within the Port Musgrave area recorded 24 snubfin dolphins sighting within the study area during 10 days of field survey during 2009 (WorleyParsons, 2010). Six incidental Australian Snubfin Dolphin sightings have been recorded between Mapoon (Cullen Point) and the lower estuary system of the Skardon River during various studies undertaken by PaCE between October 2011 and April 2015. The species show a large dietary breadth feeding on both fish and cephalopods (Parra & Jedensjö 2009). This species exhibits site fidelity and long-term associations between individuals. There is no reliable information on calving season.
The Indo-Pacific Humpback Dolphin has local populations along the Queensland coast that are small in number and discrete in geographic range (Hale et al., 2000). Habitat preference is for shallow turbid estuarine and coastal waters (Lin et al., 2013) and in particular shallow channels (two to five metres) (Hale et al. 1998), although they do range over a much larger depth range to approximately 20 m. Previous field investigations undertaken for the adjacent Port Musgrave area recorded twenty two humpback dolphin sightings within the study area during 10 days of field survey during 2009 (WorleyParsons, 2010). Coastal development is considered a threat to both humpback and snubfin dolphins, but they persist in areas with such developments, such as Moreton Bay (Brisbane) or Cleveland Bay (Townsville) (Parra, 2006).
Compared to the previous two inshore dolphin species discussed, Indo-Pacific Bottlenose Dolphins extend their habitat use into deeper, more open continental shelf waters (less than 200 m deep), including coastal areas around oceanic islands. They are usually more abundant in waters greater than 30 m deep, but do regularly occur at a number of locations (e.g. Point Lookout on North Stradbroke Island) in much shallower water (Hale et al., 2000; Chilvers et al. 2005). They are
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associated with many types of substrate and habitats, including mud, sand, seagrasses, mangroves and reefs (Barros and Wells, 1998; Hanson and Defran, 1993).
Pantropical Spotted Dolphins are among the most common dolphin species with population estimates being in the millions of individuals. Pantropical spotted dolphins feed mainly on small epipelagic and mesopelagic fish, and squids. While the location of the Project is unlikely to be an important location for the species given its preference for more oceanic waters, it is nonetheless known from the region, and it is plausible that individuals will be occasionally found there.
Table 6-8 Incidental snubfin dolphin sightings by PaCE in waters surrounding the Skardon River Date Count Notes
October 2011 3 Within the lower Skardon River estuary. January 2012 1 Within the lower Skardon River estuary. November 2014 2 Transiting between Cullen Point and the Skardon River. November 2014 1 The Skardon River mouth and inner estuary. April 2015 The Skardon River mouth and at locations offshore from the river mouth feeding 10 on schooling tuna.
6.5.4.3 Fish and Sharks
A number of shark and sawfish species are the focus of contemporary conservation efforts, and sawfishes and northern river sharks (Glyphis spp.) are a specific focus in northern Australia. The waters of the Gulf of Carpentaria contain a number of threatened shark species. Australia is considered to possibly be the last country where viable populations of sawfishes potentially remain and as such populations are of global significance (Phillips et al., 2011). The northern river sharks are endemic to Australia and parts of Papua New Guinea.
A specific risk to these species is the entanglement in monofilament gill net used by commercial fishers to target finfish such as Barramundi (Lates calcarifer) (Stevens et al., 2005; Field et al., 2013). An additional threat is from recreational fishing activities.
Speartooth Shark (Glyphis glyphis) has been recorded from the lower reaches (salinity between 0.8 and 28 ppt) of the Wenlock and Ducie Rivers and Port Musgrave, as well as the Bizant River, and a number of river systems in the Northern Territory (Peverell et al., 2006). From a limited amount of tagging work, Speartooth Sharks are considered to move up and down an estuary system with the tide and repeatedly use the same available habitat (Pillans et al., 2010). Younger sharks are generally found further upstream than older juveniles and sub-adults. Adult sharks are assumed to occur in offshore waters (Pillans et al., 2010). While it is possible that the species also occurs in other rivers of Western Cape York, dedicated surveying and observer data from commercial fishing operations to date has not documented their occurrence elsewhere. Given the habitat preference and occurrence in the Port Musgrave area the species possibly occurs in the Skardon River.
The Dwarf Sawfish (Pristis clavata) occurs on sand, mudflats and upstream estuarine habitats, including inundated mangrove habitats that the species access at high tides (Peverell, 2005; Stevens et al., 2008). There are considered to be distinct populations on the west coast, the north coast and the Gulf of Carpentaria, with no migration between these locations (Phillips et al., 2011). The species breeds in estuarine areas during the wet season with juveniles remaining in these areas up until about three years of age before migrating to other areas, with adults returning to the estuarine areas for pupping (Peverall, 2005; Thorburn et al., 2008). Given the habitat preference of the species it is likely to occur in the Skardon River and may also occur at and adjacent to the proposed BLF.
The Largetooth Sawfish (Pristis microdon) may potentially occur in all large rivers of northern Australia from the Fitzroy River in Western Australia to western Cape York and has a preference for
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river channel habitat. The species utilises both marine and freshwater habitats, but does not generally extend into coastal habitat such as the flats at the mouth of rivers, and appears to have a preference for waters of low salinity (Thorburn et al., 2004). Given the habitat preference of the species it is highly likely to occur in the Skardon River and may occur at and adjacent to the BLF. Given the salinity of the Skardon River waters during the dry season is ambient seawater (35 ppt) and the species appears to have a preference for lower salinity water, the area around the BLF is considered unlikely to constitute critical habitat for the species, at least during the dry season.
The Green Sawfish (Pristis zijsron) is considered to be widely distributed throughout the Gulf of Carpentaria; however, it has a preference for sand and mud flats outside of river mouths (Peverell, 2005). It frequently utilises very shallow water (< 1 m) and an individual animal commonly uses the same small patch of habitat repeatedly (Peverell and Pillans, 2004 and Stevens et al., 2008). Given the current information on the habitat preference of the Green Sawfish, it is unlikely to be present at or adjacent to the BLF. Individuals may occur at the Skardon River entrance shoals and at the transhipping location on the basis that adults are known to extend into deeper waters in the vicinity of river mouths.
The Australian distribution of Narrow Sawfish (Anoxypristis cuspidate) is unclear though it is most common in the Gulf of Carpentaria (Last and Stevens, 2009). In a survey of the presence of the four sawfish species in fisheries bycatch, Narrow Sawfish was the most abundant and was recorded in both the inshore and offshore set net fisheries (Peverell, 2005). Though details of its ecology are not precisely known, it probably spends most of its time on or near the bottom in shallow coastal waters and estuaries (Compagno et. al., 2006). The Narrow Sawfish inhabits estuarine, inshore and offshore waters to at least 40 m depth (Last and Stevens 2009). Inshore and estuarine waters are critical habitats for juveniles and pupping females, whilst adults predominantly occur offshore (Peverell 2005). Northern Australia, particularly the Gulf of Carpentaria (Peverell 2005), and parts of the Queensland east coast (Harry et al. 2011), contain the most viable, ecologically functional populations that remain worldwide.
Reef Manta Ray
The Reef Manta Ray (Manta alfredi) is a large filter-feeding ray circum-globally distributed in tropical and subtropical waters (Couturier et al., 2011, cited in Marshall et al., 2011). While broadly distributed, populations appear highly fragmented, likely due to the specific resource and habitat needs of this species. It is commonly sighted inshore, around coral reefs and rocky reefs in coastal areas (Marshall et al. 2009; 2011) and within areas of upwelling which provide nutrient rich waters supporting high plankton abundance.
The species predictably aggregates to particular locations such as Lady Elliot Island, North Stradbroke Island and Byron Bay in eastern Australia, for which they display a high degree of site fidelity (Couturier et al. 2011). Aggregation sites are strongly believed to represent critical habitats for this species. Reef Manta Ray has also been recorded from the Torres Strait (Couturier et al. 2011). While the presence of reef habitat and upwellings are limited in the gulf (National Oceans Office 2004a), the region comprises relatively high seasonal levels of productivity for phytoplankton and zoo plankton. (Rothlisberg and Jackson, 1982).
Pipefishes
The Gulf of Carpentaria also supports rich pipefish populations. The distribution and abundance of pipefishes in the Gulf of Carpentaria is poorly known, but it is known that the species group forms a component of by-catch in the Northern Prawn Fishery. The Project is unlikely to result in any significant impacts to pipefishes as only small amounts of potential habitat will be impacted by the Project.
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6.5.5 Fisheries
A range of recreational and commercial fisheries activities occur within the Skardon River and the adjacent foreshore areas. Prawning may also occur offshore pending the wet season flows from the adjacent Ducie and Wenlock River Catchments; however, the peak trawling activities within the western Cape York region occur further south, adjacent to Weipa.
The marine fish assemblages of the Skardon River have not previously been the focus of scientific study. However, fisheries within the Gulf of Carpentaria have been described in detail, with a significant study completed in Albatross Bay, approximately 80 km south of Port Musgrave (refer Appendix 6 in Appendix B3). The study completed in Albatross Bay provides a detailed species listing for marine fishes potentially relevant to the Skardon River study area. In addition, surveys undertaken by DEEDI were completed over three sampling events in 2009 at three locations within Port Musgrave; Ducie River (Port Development site), Wenlock River, and Namaleta Creek. From these studies 126 species were identified (Appendix B3).
The recreational and commercial fishing activities occurring in the wider region are summarised in the following sections. Further detail is provided in Appendix B3.
6.5.5.1 Commercial fisheries
Commercial fisheries logbook grid data (refer Appendix B3) describe the catch in the commercial line, net and crab fisheries in the region of the proposed development. The grid data however contains a significant area outside the development footprint and as such will significantly overestimate the potential catch from the Skardon area. The most important species caught in these grids are Spanish Mackerel (Scomeberomorus commersoni) in the line fishery, and various shark species and Grey Mackerel (S. semifasciatus) in the net fishery.
6.5.5.2 Northern Prawn Fishery
The Northern Prawn Fishery (NPF) targets Banana Prawn (Fenneropenaeus merguiensis) and Tiger Prawns (Penaeus esculentus and P. semisulcatus) and extends off Australia’s northern coast, from the low water mark to the outer edge of the Australian fishing zone (AFZ) in the area between Cape York in Queensland and Cape Londonderry in Western Australia. It is a Commonwealth Government managed fishery and is considered one of the most valuable fisheries in Australia, with a GVP of $72 million in 2007/08 (AFMA 2009).
In practice, the fishery is focussed on a number of “hotspots”, although the relative importance of these hotspots varies between years in response to climatic factors, in particular rainfall. Banana and tiger prawns are targeted at different times and generally in different locations. The tiger prawn season extends from August to November and the banana prawn season extends from April to June. The main fishing area in the region is offshore of Albatross Bay (approximately 80 km south of Port Musgrave) with very low catches or no catch in the region directly around Port Musgrave.
6.5.5.3 Gulf of Carpentaria Development Finfish Trawl Fishery
Developmental fisheries are those that use fishing gears and/or target new and underutilised species. In the Gulf of Carpentaria there is a Developmental Finfish Trawl Fishery which generally operates outside 25 nautical miles from the Gulf of Carpentaria coastline north of 15 degrees South latitude and is therefore remote from Project area activities. It is a limited entry, quota-managed, semi-demersal trawl fishery with five Developmental Fishing Permits issued since 1998; however only two were active in 2006. The main species captured include the Crimson Snapper (Lutjanus
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erythropterus) and the Saddletail Snapper (L. malabaricus) that are found on coastal and inshore reefs.
6.5.5.4 Gulf of Carpentaria Inshore Finfish Fishery
The Gulf of Carpentaria Inshore Finfish Fishery is a commercial mesh net fishery managed by the Queensland government and extends from the Queensland-Northern Territory border to Slade Point on the north-west coast of Cape York Peninsula. It has an inshore component (0 – 7 nautical miles) targeting species such as Barramundi (Lates calcarifer), and threadfin species (Polynemus sheridani and Eleutheronema tetradactylum), and an offshore component (7-25 nautical miles) targeting various shark species and Grey Mackerel. In 2006, 87 licensed fishers harvested 1,782 tonnes of fish with a landed gross value of production of $12.8 million.
Production of the key target species in these fisheries is reliant on intact and functioning inshore habitats such as mangroves and seagrass and the connectivity between habitats. There is a closed season between the months of November to February to protect the spawning stock.
6.5.5.5 Gulf of Carpentaria Commercial Line Fishery
The Gulf of Carpentaria Commercial Line Fishery is managed by the Queensland government and extends from the Queensland-Northern Territory border to Slade Point on the north-west coast of Cape York Peninsula. In 2006, 27 licensed fishers harvested 237 tonnes of fish with a landed gross value of production of $1.6 million. The main target species is Spanish Mackerel which constitutes 90% of the total catch. The reef areas in the vicinity of Pera Head, Boyd Point and Thud Point area recognised as key locations in the Weipa region for the targeting of Spanish mackerel by commercial line fishers. These locations are located over 100 km south of the Port Musgrave study area. The peak season in the Weipa region extends from August to November.
6.5.5.6 Commercial Charter Operations
Guided fishing makes a contribution to supporting recreational fishing tourism and attracts international tourists to Weipa with some of this effort occurring in Port Musgrave and Skardon River area. Approximately 12 commercial tour operators have been working in the commercial logbook data grids that encompass the study area. Catch and effort data indicates a seasonal trend in the abundance of fish in the area with April being the most productive fishing month for commercial tour operators. Monthly catch data is limited for December to February across all the years analysed, a factor most likely influenced by the wet season; a period of uncomfortable fishing conditions and unstable weather patterns.
Species composition was recorded as a measure of whole weight in the commercial charter fishery logbook program and was dominated by Snappers (Lutjanid spp.), Barramundi, and Spanish Mackerel. 6.6 Potential Impacts
The assessment of potential impacts has taken into consideration the duration of construction activities, the timing of the Project activities (dry season) and the Project design. The potential impacts of the Project’s construction and operational activities to the marine habitats, marine species and fisheries are provided below.
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6.6.1 Marine Habitats
The potential impacts to marine habitats include:
. Direct impacts to habitats;
. Decreased water quality;
. Increased sedimentation and Total Suspended Solids (TSS);
. Disturbance of PASS;
. Degradation or modification of benthic habitats; and
. Hydrological Connectivity.
6.6.1.1 Direct Impacts to Habitats
Construction of the proposed port infrastructure and haul roads will require the disturbance of fringing mangrove and saltmarsh marine communities adjoining the Melaleuca and eucalypt woodlands dominating the plateau. The footprint considered includes the proposed abutments and revetments at the upper tidal limits, conveyor trestle and quay line from which bauxite loading will be undertaken.
The proposed barge loading area and associated roll on/roll off (RoRo) facility has been designed to minimise the clearing of marine habitat as much as possible. Under the proposed footprint the barge landing facility and RoRo may indirectly impact approximately 0.4 ha of mangrove habitat (RE 3.1.1a/3.1.3). The northern and southern haul roads will result in the disturbance of approximately 20.06 ha of mangrove vegetation and 0.25 ha of saltmarsh (RE 3.1.6) vegetation and may be reduced with further design refinement. These works represent a minor local impact on mangrove vegetation which is extensive in the local region and represent <0.4% of the mangrove vegetation within a 20 km radius of the Project area. The removal of mangroves and adjoining habitat may have a very minor impact on the extent of occurrence of Estuarine Crocodile and sawfish species; however, there is abundant similar habitat surrounding the Project area and no significant impact is expected.
The BLF has the potential to indirectly impact seagrass habitat although no areas surveyed by PaCE (2014) are anticipated to be directly impacted. Pre-construction seagrass surveys within and near the Project footprint will be undertaken to confirm whether seagrass is present. Seagrass habitat may provide foraging resources for Dugong and Green Turtle. There are several other small patches of seagrass in the Skardon River estuary; however it is unlikely the extent of seagrass is of a sufficient extent to support marine fauna. Sightings of Dugong in the Skardon River are restricted to a single confirmed sighting in 2003 (Roelofs et al., 2003). There are no confirmed sightings of Green Turtle in the estuary. There is abundant more suitable habitat in the Port Musgrave area further south where both species are known to occur. In addition, the mangrove, saltmarsh and seagrass areas will be subject to the Project Biodiversity Offsets Strategy (refer Chapter 5 – Terrestrial and Aquatic Ecology and Appendix C – Project Biodiversity Offsets Strategy).
Movement of barges around the BLF and RoRo may induce altered current patterns and may lead to localised erosion of underlying soft sediments within the berth pocket, by way of increased current velocities during flood and ebb tidal flows and during maneuver of the barges and tugs via prop wash. The absence of the need for bed-levelling or dredging operations to deepen or widen the berth pocket, or access route for the barge operations along the Skardon River means overall hydrodynamic function will remain as per the existing predevelopment case. Ongoing operations
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have the capacity to alter bank stability and erosion factors. Given the potential for cumulative impacts from other proposed operations, and the proposed operational life of 12 years, further investigation into vessel wake and wave erosion will be considered as part of the detailed design work prior to construction. Further discussion is included in Chapter 19 – Coastal Environment.
The passage of vessels potentially presents a physical disturbance to fauna. Given the proposed export tonnages, passages of six to eight tug and barge combinations per day would be anticipated. At this rate vessel movements are averaged at one every three to four hours. The barging of the bauxite from Skardon Port to the offshore transhipment location will result in the generation of vessel wake waves within the Skardon River. As mangroves are present along the majority of the banks of the Skardon River any vessel wake waves are expected to be attenuated by the established mangrove vegetation and will therefore not result in significant erosion of the river bank. However, it is also noted that ongoing port operations have the capacity to alter bank stability and erosion factors (bank erosion within the Urquhart Point area of Weipa Harbour). Given the potential for cumulative impact from other proposed operations, and the proposed operational life of 12 years, further investigation into vessel wake and wave erosion potential is proposed to confirm the findings described in B3 – Marine Ecology and Coastal Processes and Chapter 19 – Coastal Environment.
6.6.1.2 Decreased Water Quality
Key potential impacts to long-term marine water quality during operations will include increased sedimentation from surface water runoff entering the marine environment, disturbance of ASS, potential spills and chemical release and shipborne liquid waste.
Surface Water Runoff
Mangrove and bank environments may possess greater silt and clay fractions as materials deposit along these shorelines. These environments are not anticipated to be affected by significant perturbations beyond the initial construction period as tidal fluctuations and strong river currents will mitigate much of this impact.
It is not anticipated that runoff from the sediment ponds at the MIA will present a significant impact to the water quality of the Skardon River. Prior to the cessation of works leading up to the wet season, product stockpiles will be depleted and any remaining product will be relocated and stored in-pit, which effectively removes the major potential source of sediment. In addition sediment will be removed (likely October/November) when ponds have naturally dried out due to evaporation. Sediment that is removed will be taken to an area where sediments will be contained, such as a mining area prior to rehabilitation. The removal of sediments will ensure that prior to the start of the wet season, the ponds will have maximum storage capacity at the start of the wet season, including the sediment storage zone. A review of the designed storage capacity will be undertaken at the completion of each wet season to determine suitability.
Operation of barges and supply vessels may generate propeller wash as sediments are mobilised from the bottom in shallower waters. Propeller wash generates increased turbidity and sediment mobilisation surrounding the immediate location of vessel operation. The influence of propeller wash is greatest at the lower end of the tidal range. Given the localised and repetitive nature of the proposed operations at the BLF, after a period of operation, the influence of propeller wash may decrease as fine sediments in the areas are mobilised, leaving coarser fractions or the exposure of underlying firm substrates (in this instance underlying clays and ironstone). No substantial impact from increased turbidity is expected on any of the estuarine species potentially present.
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Minor changes in current velocities may also be expected surrounding the mooring blocks for cyclone moorings. Localised mobilisation of soft sediments may be expected within the immediate vicinity of these features.
Disturbance of Acid Sulfate Soils
The river based sediment sampling confirms elevated potential acid sulfate soils (PASS) concentrations within the upper estuary and adjacent to the proposed BLF and RoRo. Sediments within the proposed RoRo, conveyor alignments and barge loading areas have the potential to create acid drainage problems should these be exposed to oxidising conditions. However, given the proposed piling construction methods (refer to Chapter 2 – Description of the Project) the risk is considered low. The Queensland Acid Sulfate Soil Technical Manual: Soil Management Guidelines (Dear et al., 2002) identifies piles as a low impact construction method for acid sulfate soils (ASS) impacted areas. The Australian Standard (AS) 2159-1995 − Piling Design and Installation (Standards Australia, 1995) is the guideline used to assist the use of piles in soils that contain pyrite or are saline. The guidelines also advise research on concrete performance in sulfate-rich environments.
The presence of minor ASS and PASS reported from limited shore based sampling indicates that shoreline construction, excavations and construction of any associated revetments may need to more broadly consider ASS and PASS distribution. The data reported from the vicinity of the potential barge loading and RoRo areas identified elevations within the upper 1.0 m, with little impact risks being identified at depth.
Uncontrolled Releases to Marine Environment
Spills or accidents resulting in the release of chemicals to the waterways, or directly to mangrove systems are not considered of substantial risk. This is based on limited volumes and standard approaches to use and management. The greatest risk of impact from chemical release may arise from accidental discharge of diesel to the environment during transfer of fuel to onshore storage tanks either via pipeline or operational failures. Standards and operational controls are considered to substantially limit the likelihood of such impacts.
Shipborne Waste
Excessive amounts of sewage entering into closed and semi-enclosed water bodies can cause eutrophication, algal blooms and oxygen depletion. Research has shown that even in the absence of any onboard treatment before discharge, impacts would be temporary because of the small quantities involved (approx. 12 L per person per day from a crew of around 25 to 30 typical of a Panamax ship), rapid dilution in the sea, high biodegradability and low environmental persistence of the wastes. Demand for key nutrient elements such as nitrogen may be so high that bio-available forms (ammonium and nitrate) are recycled on time scales ranging from minutes to hours.
The OGVs loading at the Skardon River transhipment area would be expected to be equipped with appropriate STPs, in accordance with international standards. The locally operating vessels, including tugs and the floating cranes, will also be fitted with appropriate STPs, with only treated effluent then being disposed of to sea in accordance with national and international standards (Transhipment Services Australia, 2015a).
Given the small releases only of processed wastewater from vessels off Skardon River, any impacts associated with sewage discharge would be highly localised and transient.
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6.6.1.3 Degradation or Modification of Benthic Habitats
The benthic assemblages have developed their distribution according to physical substrates, current dynamics and a complex relationship of prevailing water quality regimes and benthic light availability. Although the significant variability in ambient conditions may infer a high resilience to water quality changes, it should be noted that the respite between periods of impact becomes increasingly important the further conditions wane from optimal for long-term survival/growth. While it is important to consider that provision of respite during extended construction programs may be of importance to some benthic communities, given the relatively short construction period for this Project, no respite periods are currently proposed. It is also noted that the Project proposes to have respite periods of approximately 4 months every year, resulting from shut down over the wet season.
Surveys by PaCE have concluded a dominance of bare substrates offshore at the proposed anchorage areas (96-99 % bare substrate), with live cover being in the order of 1 – 4 %. The proposed bulk carriers for transhipment will arrive at the area and anchor. Anchoring provides direct disturbance to the substrate and impact to benthic biota. Continual anchoring within the area will act to physically remove or damage portions of the existing community. The typical extent of anchor damage would follow a 4-5 m wide corridor. As the chain is deployed the anchor would move to the sea bed. A portion of the anchor chain would be located on the seabed and movement (drag) will disturb sediment and potential benthic biota within that zone. Upon retrieval the anchor and chain would be lifted from the seabed with some additional disturbance. The impacted areas would be expected to recover over a short period of time, supplied by similar low density habitat adjacent.
Propeller wash will also be generated at the transhipment area as for the barging process within the Skardon River and BLF. While the bauxite barges will not have sufficient draw to impact the substrates due to depth, the bulk carriers will be loaded and maintain a substantial draft which will bring them closer to the seabed. Given the processes expected within shallow water from the tugs, the propeller wash from the OGV is also expected to provide erosive forces due to increased bed velocities and bed shear values. Given the prevailing substrates, a process of bed armouring may be expected within the transhipment area. As finer sediments are winnowed from the primary anchoring and departure areas, the bed will increase in particle size and increase the bed shear stresses required to move materials into suspension. Over time the impact of propeller wash on bed disturbance, erosion, water column suspension and altered deposition processes will decline.
6.6.1.4 Hydrological Connectivity
While the Port development activities will not directly or indirectly alter the hydrology of the Skardon River, development of culverts and road crossings may be required across two tributaries within the upper catchment. Construction would occur during the dry season when the tributaries are basically dry, and would therefore be extremely unlikely to impact access by either Speartooth Shark or sawfish. By designing crossings and culverts to maintain hydrological connectivity during the wet season, any impacts on the passage of the sawfish and Speartooth Sharks between saline and freshwater habitats would be minimised. Further discussion regarding hydrology/hydraulics is included in Chapter 10 - Water Resources (hydrology and hydrogeology) Chapter 11 – Flooding and Regulation Structures, Appendix E1 – Groundwater Technical Report and Appendix E2 – Surface Water Technical Report.
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6.6.2 Marine Species
It is not expected that the construction or operation of the Project will have any significant long- term direct or indirect impacts to marine fauna in the area. The Project footprint is not within critical or high value feeding and/or nesting habitat for marine turtles, dolphins, Dugongs or whales. Surveys undertaken within the Skardon River have illustrated that the area is not densely populated by marine fauna and potential foraging in the area directly associated with the proposed BLF and RoRo is not reduced in comparison to other areas throughout the river.
The potential impacts to marine fauna species include:
. Increased underwater noise and vibrations;
. Direct fauna strike;
. Increased lighting; and
. Increased shading.
6.6.2.1 Increased Underwater Noise and Vibrations
When aquatic animals are subject to introduced noise sources their behavioural patterns may change. This is called a behavioural response and may include, among many possible responses, avoidance of the area, change in vocalisations, and parent/offspring distance modification. At increased levels underwater noise may also cause temporary hearing impacts, permanent hearing impacts or other tissue trauma, up to and including death. Activities associated with construction and operations in the marine environment have the potential to displace local marine fauna including marine turtles, cetaceans and sawfish from habitat and interrupt behaviours through the creation of underwater noise.
Cetaceans are well studied and have been found to avoid some human sound sources for ranges of several kilometres, abandoning valuable habitat in the process (Tyack 2008). For mobile marine animals, avoidance behaviour is the common response to underwater noise when that noise reaches a certain threshold, and this is well established in the peer reviewed literature (Nowacek et al., 2001; Ng and Leung, 2003; Hodgson and Marsh, 2007; DeRuiter and Doukara, 2012). Jefferson et al. (2009) identified that Indo-Pacific Humpback Dolphins avoid areas during pile driving but return once construction ceases. The area where piling is proposed for the Project is limited to the barge landing area within the Skardon River.
Matrix Acoustics has calculated underwater noise levels from the different port construction and operational activities (refer Table 4-13 and Table 4-14, Appendix B3). Following the approaches to underwater impact assessment published by Southall et al. (2007) a screening for underwater noise impact has been undertaken based on the calculated noise levels.
Given the calculated noise profiles and conservative application of the adopted screening criteria, permanent hearing loss to cetaceans may be expected over a distance of 100 - 200 m from the pile driving activity depending upon the pile type. While temporary impacts and behavioural disturbances may extend to between 1,000 m and 2,000 m. Potential low level behavioural responses may extend for many kilometres due to pile driving, and over a very limited extent from vessel activity and during operations. These finding generally corresponds to the findings of David (2006) and Bailey et al. (2010), which outline that injury to a dolphin from pile driving activities is limited to an area of approximately 100 m from the source, although behavioural responses may occur over an area of many kilometres (David, 2006; Bailey et al., 2010).
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Doug Cato and John Lewis (pers. comm., 2015) suggests that the acoustic propagation environment in the Skardon River at the proposed development site would be exceptionally poor, due to factors such as shallow water, muddy bottom, high turbidity and lack of any substantial direct transmission pathways. John Lewis (pers. comm, 2015) does not expect “any tangible effects beyond a few hundred metres at best, for any pile driving within the river itself”. This comment agrees with the predictions presented above and observations made by David (2006) and Bailey et al., (2010).
Underwater noise may also be generated by vessel movements. Surface shipping is considered to represent the most widespread source of low frequency (< 1,000 Hz) anthropogenic noise in the marine environment. Concern emanates around the possibility that such noise may mask echolocation vocalisations or communications; acoustically mask prey; lead to separation of calves from mothers; or if intense and localised, alienate animals from preferred aggregation sites or migratory pathways. Many of the noted concerns have limited relevance for the Project, given the transhipping location relatively close to shore and away from any known aggregation areas. In addition, the creation of noise does not necessarily mean that a negative impact occurs. The co- existence of dolphins at a large number of locations on the Queensland east coast at or directly adjacent to busy port facilities (i.e. Brisbane, Gladstone and Townsville) where vessel movements are substantially greater than proposed for the Bauxite Hills Project provides an indication that animals can adapt to this disturbance and maintain viable populations.
Dugong are also potentially sensitive to underwater noise, and construction activities such as pile driving. Pile driving and vessel activities within the vicinity of seagrass meadows has the potential to temporally drive dugong from the area. However, John Lewis (pers. comm, June 2015) indicates that “most of the noise energy from pile driving (approximately 200 Hz) is at frequencies below the threshold of hearing for dugongs.” and as such impacts may be more related to physical disturbance than noise profiles. Given the lack of any substantive seagrass meadows, and the limited number of historical Dugong sightings in the area (1 sighting in 2003), significant impacts on this species is not expected.
6.6.2.2 Direct Fauna Strike
Within eastern Australian waters, boat strikes are responsible for injuries and death to marine turtles, dugongs, whales and sharks to differing degrees. The Project will increase the number of vessels active in the Skardon River area during construction and increase the number of vessels during the operational phase. High vessel traffic in shallow coastal waters has the potential to seriously injure or kill marine fauna, including dolphins, turtles and dugongs (Parra and Arnold 2008; Limpus 2009; and Miller and Limpus 2012). Vessel strike of marine fauna is predominantly caused by fast moving recreational and commercial vessels (Ross 2006). The vast majority of vessel movements around the port will be slow (non-planing speeds of less than 6 knots). The Project will use existing transit routes within the region and hence will not change the spatial scale of potential overlap between shipping and marine megafauna.
Turtles may encounter vessels within the proposed channel alignments and during offshore operations. Displacement of turtles due to the passage of a vessel is anticipated to be relatively short lived, with individuals diving to avoid vessels in the immediate vicinity. Research has identified visual cues over noise induces avoidance behaviour in turtles, making reduced speeds the most appropriate tool for prevention of boat strike incidents (Hazel et al., 2007). The size, displacement and lack of mobility of operational vessels associated with the Project will necessitate a slow speed when operating. Barges and supply vessel operations do not present a substantial risk of vessel strike with turtles. Vessels at risk of collision with marine fauna (small survey or service vessel) will be used on the Project infrequently. With operational access and speed limit zones in place, a low impact upon marine turtles is anticipated.
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Dugong mortality by boat strike from fast moving vessels planning in shallow water is well documented (Groom et. al., 2005). Speed limits for fast moving vessels in designated transit areas can effectively mitigate potential impacts. Slow moving displacement vessels such as barges and tugs as proposed within this Project do not pose a substantial risk. With speed limits in place for particular types of vessel, and the operation of all marine craft to agreed vessel access channels, a low impact upon Dugong is anticipated.
The potential for boat strike on whales is similar for Dugong in that a key determinant in the potential for collisions between vessels and cetaceans is the speed of the vessel (Vanderlaan and Taggart, 2007; Wiley et al., 2011). As whales do not inhabit the estuarine areas of the Skardon River and the slow moving displacement vessels that will operate in the transhipment this is minimal risk of boat strike to whales. The risk of boat strike on dolphins is considered minimal due to their mobility and ability to quicker response to disturbances. The slow moving displacement vessels operating in the Skardon River and the transhipment area are similarly not anticipated to pose a risk to dolphins.
Sawfish are typically bottom dwelling species and as such it is unlikely that they will be impacted by barging and shipping movements. Given the slow speed of vessel (barge) movements within the operational port limits, vessel strike on cetaceans is not considered a risk requiring specific mitigation.
6.6.2.3 Increased Lighting
Artificial light in general has been identified as a global environmental challenge that significantly threatens components of biodiversity (Hölker et al., 2010; Lyytimȁi, 2013). The life cycle of marine turtles is particularly susceptible to light pollution when it occurs at or adjacent to nesting areas (Witherington, 1992; Kamrowski et al., 2012, 2014a and b). A direct line of sight from the light source to the nesting beach is not necessary to illicit a response from hatchling as they respond to light glow (Kamrowski et al., 2014a). Lights at or adjacent to a nesting beach can result in turtle hatchlings heading inland rather than into the ocean with subsequent mortality. Lights adjacent to nesting beaches can also result in hatchlings entering the ocean safely, only to re-emerge closer to the light source. The impacts of artificial lighting are reduced during the full moon period, but enhanced due to cloud cover (Kamrowski et al., 2014a).
Three sources of artificial light from the Project were considered in this assessment:
. Light from the mine and accommodation camp (i.e. inland operations);
. BLF and MIA (i.e. operations beside the Skardon River); and
. Lighting from the transhipment site, including during transhipment operations (i.e. operations on the Skardon River and out to sea).
Navigation lights from moving vessels or navigation buoys were not considered to be a plausible impact.
The mine accommodation camp and mining pits are located inland from the Skardon River and as such these infrastructure are not expected to create increased lighting that will impact on marine fauna.
The MIA, BLF and RoRo are located adjacent to the Skardon River; however, the distance to the nearest area suitable for Flatback Turtle nesting at the mouth of the Skardon River is approximately 8 km. Native vegetation screens the location of the infrastructure from the nesting beaches which
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further reduces the risk of impacts from increased lighting. As such the Project is not expected to create increased lighting that will impact on nesting turtles.
The transhipment process will occur offshore at designated transhipment anchorages. Additional lighting on the barge, and potentially the bulk carrier may be required. These activities will occur approximately 9 to 12 km offshore. Metro Mining will adopt a ‘turtle-friendly’ lighting approach to vessel and barge lighting to minimise light spill potential.
6.6.2.4 Increased Shading
Given the absence of seagrass meadows within the Project’s disturbance footprint, and the general distribution of seagrass in the broader study area the impacts of shading are not considered a significant process.
6.6.3 Marine Pests
Marine pests have the greatest potential to be introduced during construction activities, with a lower risk continuing during operations. Marine pests can enter the environment through ballast waters and biofouling of marine vessels and as such effective biosecurity measures are needed to maintain the pest free status of the area. Marine pests are species with invasive traits that can cause significant adverse impacts to marine industries, the environment, human health and or amenity if introduced, established or translocated within Australia, as well as generating substantial costs for eradication attempts or ongoing management.
6.6.3.1 Ballast Water
During the construction phase, shipping and marine vessels will be contracted to supply equipment for the construction activities. Marine species and pests can be translocated to and around Australia via biofouling on vessel hulls, in marine sediments and in damp or fluid filled spaces (niche areas) such as anchor lockers, bilges, sea chests or internal seawater systems. Pests can successfully establish in the new environment after discharge from a conveying vessel. The risk of vessels spreading these pests can be reduced by incorporating practices that minimise the build-up of biofouling into routine vessel maintenance programs.
A feature of OGV operations is the use of significant quantities of ballast water, primarily as a cargo substitute for those ships arriving (empty) to take on cargo at a terminal. Under the Australian ballast water management regulations, all ballast water arriving in Australia from overseas is considered 'high risk' and so banned from discharge in Australian waters. In general terms, ships are required to undertake ballast water exchange at sea, such that water taken up from shallow, coastal or littoral waters overseas is replaced with water sourced from the open ocean, considered less likely to harbour marine species of potential quarantine concern. To be considered effective, the ballast water exchange must be conducted outside Australia's 12 nm limit. The requirement to discharge ballast water outside Australia's 12 nm limits the potential for pest marine species to enter the waters in and adjacent to the Skardon River.
6.6.3.2 Biofouling
Along with other IMS transport vectors, such as ballast water, biofouling is a quarantine concern because of the risk that a vessel or other object is carrying fouling and may act as the means of transport for a potential marine pest species into Australian waters, or between different regions within Australia. Not all fouling species represent a biosecurity threat, and given the millions of movements of vessels over many hundreds of years, many fouling species have already established
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broad geographic distributions (i.e. the ‘cosmopolitan’ and ‘cryptogenic’ species). Some fouling species; however, do pose significant quarantine risks to Australia and potentially to Skardon River.
All vessels have some degree of biofouling, even those which may have been recently cleaned or had a new anti-fouling coating applied. In general terms, the longer a vessel has been in water, the greater the size and complexity of its biofouling community.
In essence, the biofouling which may be found on and in a vessel represents a cumulative and integrated history of the vessel’s design, construction, maintenance and operations. Each of these aspects introduces particular biofouling vulnerabilities.
By contrast, non-trading vessels, particularly those such as types typically engaged in port and coastal development projects, are considered by the DAWR to represent high biofouling-mediated risks. In recognition of these elevated biofouling risks, vessels of this type are usually subject to specific biofouling cleaning and inspection requirements as an enforceable condition in order to work on marine and coastal projects in Australian waters, as is expected to be the case for any such vessels engaged in the Project development and maintenance activities.
Harbour craft, such as tugs and barges, may become excessively fouled if operating cycles are interspersed with extended periods of inactivity. This level of fouling will not be a marine biosecurity threat if the subject vessel remained in the same location, as the fouling assemblage will represent locally available species. Thus, there will be no translocation potential should any of the locally-sourced biota be a marine invasive species. Some degree of risk will arise; if a fouled harbour craft arrives at Skardon River from some other, distant location.
6.6.4 Fisheries
The commercially important species found in the study area include; Barramundi (Lates calcarifer), Blue Threadfin Salmon (Eleutheronemna teradactylum), King Threadfin Salmon (Polydactylus macrochir), Blacktip Shark complex (Carcharhinus limbatus/tilstoni) and juvenile Grey Mackerel (Scomberomorus semifasciatus). Species of recreational importance such as Giant Queenfish (Scomberoides commersonnianus) and Barramundi were identified and these stocks currently support commercial charter operations.
The commercial and recreational fisheries resources of the study area may be affected by:
. Displacement of fishing effort due to construction or operational vessel movements; and
. Establishment of a 200 m exclusion zone around the barge facilities.
The spatial distribution of the commercial fishery includes the western beach shoreline north and south of the Skardon River entrance, and minor effort inside the estuary, including some crabbing. The commercial fishing effort in the inshore net and crab fisheries of the area is small relative to the rest of the Gulf and has been declining over the last decade. Despite the potential for temporary displacement, a major impact due to the development of the Project is not be anticipated.
The proposed vessel anchorages and transhipment locations offshore of the Skardon River are located inshore of an identified minor prawn catch area. The most profitable prawning grounds are located further south adjacent to Weipa. Impact upon prawn fisheries from the Project is considered minor.
The Project will not create a significant loss of intertidal or subtidal habitat and the passage of fish within and between freshwater, estuarine and marine systems will not be influenced by barriers, or if barriers in the form of creek crossings are required, appropriate fish passages will be
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incorporated. Further, as bed-levelling and dredging is not proposed for this Project, the impacts upon fisheries habitats are considered minor.
6.6.5 Summary of Impacts to Marine Ecology
The potential impacts to marine ecology as a result of the Project include:
. The clearing of 20.5 ha of mangrove and 0.25 ha of saltmarsh vegetation providing potential habitat for Estuarine Crocodile;
. Potential indirect impact of approximately 0.4 ha of potential seagrass community which may provide foraging habitat for Dugong and Green Turtle;
. Construction of the boat loading facility may cause disturbance of ASS and have localised noise impacts on marine fauna;
. Vessel movements in the Skardon River and to the offshore loading facility may cause bank erosion, increased sedimentation in the Skardon River and damage benthic habitats including seagrasses;
. Vessel movements in the Skardon River and to the offshore transhipment area may provide noise impacts and potential for vessel strike of Dugong, marine turtles, Australian Snubfin Dolphin and Indo-Pacific Humpback Dolphin; and
. Potential introduction of marine pest species.
These impacts will be mitigated under measures incorporated and monitored within the Project’s EMP (Appendix K) and are considered to be minor in extent. Assessment under the EPBC Act Significant Impact Guidelines 1.1 (DotE, 2013) indicate there will be no significant residual impacts as a result of the Project’s activities.
The greatest cumulative impact to the marine environment associated with the joint development of this Project and the SRBP may arise from the increased boat traffic in the Skardon River estuary and potential impacts to increased turbidity, erosion of benthic communities and banks, and collision and noise impacts on marine fauna.
Based on the preceding significant impact assessments of marine fauna species no significant residual impacts to threatened or migratory fauna are predicted to occur as a result of the Project’s activities. Therefore, no environmental offsets are required under the Queensland Environmental Offsets Policy. Nevertheless biodiversity offsets will be required for the Project to compensate for any significant, residual biodiversity values listed as Matters of State Environmental Significance (MSES) which includes limited habitat for marine species (e.g. clearing of mangrove habitat).
To fully address the Projects offset requirements a Biodiversity Offsets Strategy Report has been prepared (Appendix C). This report evaluates both MNES and MSES offset requirements, including a Significant Impact Assessment for MSES using the Queensland Environmental Offsets Policy: Significant Residual Impact Guideline (SoQ, 2014) to determine the extent of offsets required. Among the offset delivery options considered for the Project that will benefit local marine ecology is support for marine turtle nest monitoring (through the Mapoon Land and Sea Rangers) and financial contributions to the Nest to Ocean Turtle Protection Program. For further detail refer to Section 5.13 in Chapter 5 – Terrestrial and Aquatic Ecology and Appendix C.
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6.7 Cumulative Impacts
In terms of the marine environment, the only project considered to have a cumulative impact is Gulf Alumina’s SRBP. Conceptually, cumulative impacts in the marine environment range from existing impacts from recreational and industrial uses i.e. prior impacts of similar types, to complex interactions of environmental stresses due to multiple (and differing) impacts. The latter is the case for the SRBP and this Project and is relevant for considering cumulative impacts generated from the marine facilities and operation proposed by both projects.
The SRBP is proposing to establish a similar operation to this Project on the Skardon River that represents a similar investment in infrastructure and target tonnages. SRBP is proposing a purpose- built barge operating facility from the existing jetty infrastructure areas, and will undertake significant bed-levelling to improve barge access over the ebb tide bar. The Project will require some additional areas of clearing for the BLF and RoRo, but does not propose any bed-levelling activities. The construction process for both projects is similar with regards to barge infrastructure. A short construction period during the dry season will be targeted by both operations. The SRBP facility is situated at the start of seagrass habitat distribution, and as such less seagrass will be passed by barges and vessel traffic.
The combined operational scenario will present a substantial increase in vessels. To meet the basic annual tonnages and weekly bulk carrier loading targets described by the proponents, up to 100 barge movements are required within the Skardon River each week (~3,600 movements annually). These movements will be accompanied by additional movements associated with fuel and materials supply.
Bulk carriers and coastal freighters service the existing trade requirements within the Gulf of Carpentaria for bauxite export, fuel, cattle and general supplies. These vessels operate within designated shipment routes several km to the west of the proposed transhipment locations. The transhipment areas are both undeveloped locations largely undisturbed by anthropogenic processes.
Approximately 140 bulk carriers are required to service both projects each year (70 each for SRBP and the Project). The nearby port of Weipa processes approximately 500 bulk carriers annually, exporting some 30 million tons of bauxite. The additional carriers required for the SRBP represent an approximate 14 % increase in bulk carrier movements for the region. A further 14 % is attributable to the Project, increasing bulk carrier movements within the wider region by nearly 28% (both projects combined).
A number of potential direct impacts on marine assemblages have been identified and need to be considered in a cumulative sense:
. Barging and other boat operations impacting seagrass and mangrove systems;
. Discharges to the marine environment from spillages affecting water quality;
. Barging of bauxite and use of support vessels generating propeller wash;
. Transport of personnel and materials to project areas
. Construction activities in or near marine areas generating underwater noise;
. Projects’ lighting; and
. Marine pests.
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6.7.1 Predicted Cumulative Impacts
6.7.1.1 Seagrasses and Mangroves
Based on the Metro Mining’s base case, the addition of the SRBP presents a ~30 % increase in mangrove disturbance (~0.2 ha) due to mangrove clearing to facilitate the construction of marine facilities. Both operations also propose storm water releases from sediment dams during the wet season. These impacts are localised in extent and represent relatively small areas of mangrove. On a local reach scale, impacts may be considered cumulative (i.e. reducing refuge or feeding habitat); however, on an estuary wide scale, the impacts may not appear to interact.
While not presently surveyed within the construction footprints, seagrasses have been identified adjacent to the proposed development footprints for both Projects. Seagrasses are also present within shallow water environments along banks and adjacent sand bar features where the water is shallow enough to allow sufficient benthic irradiance (sunlight). Both projects have the potential to induce deposition and minor erosion over adjacent seagrass beds due to propeller wash when maneuvering. The increased passage of vessels within the upper estuary and the necessary crossover of utilisation given the same navigation route is expected to result in cumulative increases in seagrass impact.
Both Projects may directly disturb seagrasses during construction, or lead to elevations in turbidity, and sediment deposition. Light availability may also decline over the construction period. However, tidal fluctuations and strong river currents will mitigate much of this impact over a short timeframe. The seagrasses within the Skardon River have adapted to variability in turbidity and light regimes. During excavation and construction associated the Projects, elevations in turbidity and associated deposition may be expected. The mobilisation of silts/sediments during construction is anticipated to impact the immediate development area; however, the temporal extent of the impact is expected to be short lived due to the tidal fluctuations and strong river currents.
6.7.1.2 Propeller Wash
It is anticipated that both projects will utilize the same (or near enough) channel alignment and when combined, the effect of both projects will result in an increase of propeller wash within the navigation channel. This cumulative effect will potentially present an increased localised impact to adjacent seagrass beds associated with propeller wash. Propeller wash has been modeled and described as a low impact process resulting in low level increases in suspended sediments which occur infrequently, and over a short duration. Given the dominance of sands and gravel fractions within the navigational channel, the more frequent passage of vessels within this area will likely increase the process of bed armoring. This will result in the finer fractions being winnowed resulting in a concentration of sediments which are less prone to mobilisation.
The operation of transhipment zones will be duplicated, as will the potential for propeller wash during departure of the bulk carriers. However, given an absence in significant benthic habitat, the localised impact of propeller wash, the broad expanse of immediate alternative habitat and the distances between the two operations, the impacts attributable to propeller wash within the transhipment areas may be considered separate processes and an effective increase in marine pressures will not occur. The distances between the two locations will facilitate mitigation of impacts. Propeller wash impacts from the transhipment process are not considered cumulative.
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6.7.1.3 Water Quality
The relatively close proximity of both projects in the Skardon River could result in a cumulative impact to water quality due to construction and operational spillages or chemical releases. This is particularly the case given the ebb and flood of the river whereby the tides will move any impacts up or down stream past the other operations. Generally the likelihood of such events occurring are small, and with appropriate mitigation practices and operational standards any increase will be of a minor concern.
It is not anticipated that runoff from the sediment ponds proposed by Metro Mining and Gulf Alumina will present a significant impact to the water quality of the Skardon River. Both projects are proposing remove sediment from the sediment ponds prior to the onset of the wet season when the ponds have naturally dried out due to evaporation. Both Projects are proposing to take sediments to an area where sediments will be contained, such as a mining area prior to rehabilitation. The removal of sediments by both Projects will ensure that prior to the start of the wet season, the ponds will have maximum storage capacity at the start of the wet season, including the sediment storage zone. As such no significant cumulative impacts to water quality are expected to occur as a result of the sediment ponds overflowing.
Whilst the increase risks of hydrocarbon spillages may be considered of higher importance given the doubling of infrastructure and hydrocarbon movements through the river it is unlikely that two significant spill events would occur at the same time. Notwithstanding having two operations capable to respond to a larger spill event will act to reduce the overall cumulative risk.
As for propeller wash the two proposed transhipment locations would generally experience only localised impacts to water and sediment quality. The sites are separated over several kilometres and the risks of potential pollutant releases are perceivably very small. Water and sediment impacts from the transhipment process are not considered cumulative.
The threats from a larger more significant hydrocarbon spill due to two operators is not anticipated given the rarity of such events. However, having access to dual resources for spill response may limit operational impacts of a spill overall.
6.7.1.4 Boat Strike
When vessel based activities overlap with habitats utilised by dugong and marine turtles they are at particular risk from boat strike, which can result in injury or mortality. Marine turtles and Dugong are vulnerable to boat strike when they are at the surface breathing and resting between dives. It is commonly accepted that vessel speed and water depth are the main factors affecting the risk of boat strikes with faster vessels in shallower water posing a greater risk. Annually, boat strike is one of the most significant known causes of human-induced dugong mortality (Greenland and Limpus, 2008).
There is current scientific evidence suggesting that death and injury caused by boat strike has a significant impact on dugong populations in Queensland (Grech and Marsh, 2008). A recent study has found the reaction time of dugongs does not change in accordance with the speed of an approaching vessel and therefore faster moving vessels have a greater probability of causing dugong mortality (Hodgson, 2004).
Slow moving vessels such as tugs and barges are considered to pose an inherently low risk of boat strike to dugong and marine turtles in the Skardon River. However, given the number of tug and barge sets (Metro Mining) and self-propelled barges proposed by Gulf Alumina the risk of potential boat strike increases. Notwithstanding there are limited records of dolphin species and Dugong
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occurring in the Skardon River and therefore the increase in vessels numbers is not anticipated to have a significant impact on critical and even non-critical populations of these species.
6.7.1.5 Construction and Boat Noise
Activities associated with construction in the marine environment and operations, in particular vessel movements, have the potential to displace dugong and cetaceans from critical habitat and interrupt critical behaviours through the creation of underwater noise. Cetaceans have been found to avoid some human sound sources for ranges of several kilometres, abandoning valuable habitat in the process (Tyack, 2008). There are a number of underwater noise sources that may impact on cetaceans and dugong. These include pile driving and vessel traffic.
Noise from piling activities associated with both projects has potential to cause disturbance to cetaceans and Dugong that may occur within the construction area or adjacent waters. While information is limited, Jefferson et al. (2009) identified that certain species of dolphins avoid areas during piling activities, and in particular pile driving, but return once construction ceases. Overall, it is considered that disturbance to cetaceans and Dugong will occur during the construction phases of both projects; however, it is anticipated that impacts will be infrequent and of short duration.
Noise generated by vessel activity can also change the behaviour of dugong and result in alienation from important habitat. Hodgson (2004) found that dugongs were less likely to remain feeding if a boat passed within 50m than if it passed at a greater distance. These movements occurred in response to boats passing at all speeds, and at distances of less than 50 m to over 500 m. Such disruptions to feeding can affect the health of a population if they occur at significant levels. However, if animals can move to suitable nearby habitat then this may largely mitigate impacts from disturbance (Gill et al., 2001). In the case of Skardon River there is no existing high value dugong (seagrass) habitat occurring in areas affected by the proposed projects. The cumulative impacts of projects affecting the Skardon River will increase the number of noise sources and duration of noise created within the river. This in turn has the potential to displace Dugong and cetaceans from habitat areas for longer periods of time.
6.7.1.6 Project Lighting
Lighting from the two projects will result in a cumulative increase in lighting footprints depending upon their stages of development. However, given extensive buffers between nesting beaches from vegetation and topography, the resulting light impacts from proposed mining, barge facility and worker accommodation areas is not anticipated to result in a cumulative increase in lighting impact along turtle nesting beaches. Offshore lighting during transhipment may provide a cumulative effect, although over distances of between 5 and 15 km, the resulting light impacts are considered minor. 6.8 Management and Mitigation Measures
6.8.1 Management of Impacts
The process of selecting the proposed locations for Project infrastructure has considered avoidance of potentially significant habitats and adjacent environmental management areas. The following outline proposed management measures in respect to marine ecology.
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The management measures that will be considered as part of the continuing development of the Project include:
. Minimise disturbance zone of mangroves as much as practicable within Project footprint and clearly cordon off adjacent areas from disturbance;
. Conduct seagrass surveys within and near to Project footprint prior to construction activity commencing;
. Limit vessel passage over known seagrass habitats and conduct biannual seagrass monitoring within Skardon River;
. Where necessary and practical deploy ‘silt curtains’ to screen seagrass habitat adjacent to construction footprint to control impact of sediment plumes cause by construction activity;
. Native riparian vegetation health adjacent to the BLF will be monitored and maintained. This is considered especially important for mangrove vegetation as it will help to prevent bank erosion due to vessel movements;
. The RoRo ramp will be located at the narrowest section of mangroves to limit the extent of the clearance footprint;
. Impose suitable vessel speed limits (4 to 6 knots) and operational area restrictions to minimise any potential increased bank erosion due to the barging activity. This will be defined based on the barge vessel size and capacity as well as the transport frequency; and
. General Project staff will be restricted from the beaches associated with turtle nesting to the west of the Project area.
Potential impacts and management measures in regard to waste are discussed in Chapter 14 – Waste Management.
Potential impacts and management measures in regard to shipping are discussed in Chapter 17 – Transport.
Potential impacts and management measures in regard to coastal dynamics are discussed in Chapter 19 – Coastal Environment.
6.8.1.1 Increased Underwater Noise and Vibrations
Underwater noise generated by construction of the barge landing will be temporary. The program of construction will target the dry season, and be completed over a period of two to three months. This timing will assist in minimising interactions with marine fauna such as the sawfishes and Speartooth Shark, which may access the estuary system for pupping between the late dry/early wet season and through the wet season. The following mitigation measures will be applied during the pile-driving program to reduce the potential impacts on marine fauna:
. Piling will be carried out during the day only and noise will be attenuated by appropriate engineering measures where practicable;
. Correct specifications of piles and the pile driver for the proposed constructions works will be used to avoid excessive energy requirements to achieve pile penetration;
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. A 500 m safety exclusion zone will be established around piling works. This zone will be confirmed by measuring noise from initial marine piling operations and redefining safety exclusion zone if required;
. As part of the Significant Species Management Plan all staff will be educated on the potential presence of marine megafauna and reporting of observations to the Environmental Officer;
. Trained marine megafauna observers will be onboard the pile driver to identify any cetaceans (or other megafauna) present in the area of construction, and pile driving activities will not start if an animal is identified within 500 m of the pile driver when operating. Construction will not recommence until the fauna move out of the exclusion zone. Observations of marine fauna will be recorded;
. All impact and vibratory piling works will adopt a soft start approach. In the first instance, this could incorporate piling commencing at low energy levels and then building up progressively to full impact force. If this is not possible, then a single pile impact could be conducted followed by another single pile impact after about five minutes. Then normal piling can then begin after another 10 minutes, so as to allow any marine mammals who may be approaching to leave the area. If either of the soft start approaches described is not practically feasible for operational reasons, then an acoustic deterrence device may be used to allow marine fauna to leave the area prior to commencement of full piling; and
. Marine-based pile driving activities will take place during daylight hours.
Operations and the resulting increased underwater noise from barge and tug movements are proposed for approximately 32 weeks of the year, being closed during the wet season. The vessel management plan will avoid shallower waters, restrict vessel movements and speeds.
6.8.1.2 Direct Fauna Strike
Marine operations will be conducted in compliance with the vessel access and speed limit plan (ranging from 4 to 6 knots) provided within the Project Environmental Management Plan (EMP: Appendix K). Vessel movements will be restricted to dedicated zones, areas of sufficient water depth, and at speeds suited to safe vessel operation and minimal environmental impact. This initiative will minimise as far as practicable interactions (collisions) with marine species. Observations of marine fauna will be recorded (including species and location) and incidences of direct interaction such as vessel strike, or near vessel strike reported to the site environmental officer.
6.8.1.3 Increased Lighting
It is not predicted that the Project will result in an altered light regime sufficient to alter the sea finding behaviour of locally nesting marine turtles, or cause aggregation at the proposed transhipment location. However, if necessary a contingency plan to reduce light spill can be implemented for the Project. Methods to reduce the impacts of lighting need to remain considerate of occupational safety and navigation requirements thus the following measures will be taken:
. Only essential lighting will be included in development;
. Turtle friendly lighting will be used where necessary and possible with an initial preference for long wavelength lights (560-700 nm) to be used wherever possible, where this is not possible, low pressure sodium (LPS) lights or LEDs should be considered. If LPS are used, then amber light filters will be installed;
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. Lighting design will consider techniques that limit turtle impacts and include light shrouding where necessary (i.e. be well shielded, full cut-off and downward directed type fixtures);
. Luminaries will be mounted low in the vertical plane and use the lowest intensity for the task;
. Intense lights or clusters of lights will be avoided wherever possible;
. An automated control system will be implemented to reduce or switch off unnecessary lighting;
. White lights that emit ultraviolet light will be avoided, strong blue or green spectral elements will also be limited;
. An illumination plan will be developed describing each light source in terms of its purpose, location, footprint, intensity and spectral composition and document steps to avoid, mitigate and manage the impacts of each source;
. Install timers and motion detectors wherever possible;
. Periodic inspections, audits and corrective management of light sources will be undertaken; and
. Inductions for staff and contractors will include relevant information on marine turtles.
6.8.1.4 Increased Shading
Given that shading is expected to only impact the small area of habitat immediately adjacent to the BLF specific management and mitigation measures have not been proposed.
6.8.1.5 Marine Pests
The DAF released guidance into the design, operation and reporting of marine pest monitoring within Australia via the Australian marine pest monitoring guidelines and Australian pest monitoring manual. These documents will be used to establish a practical monitoring, management and reporting program for introduced marine pests as required in the draft Project EMP. The objectives of the Marine Pest Monitoring Program will be:
. Early detection of introduced marine pests into the Skardon River; and
. Implementation of an introduced marine pest emergency response where an introduced marine pest is detected.
The draft EMP (Appendix K) provides an overview of the monitoring program and the timing of the monitoring program components.
Shipping vessels are a recognised vector for the transfer of organisms which may pose both marine and terrestrial quarantine risks. These include vertebrate and invertebrate animals, plants and pathogens, which may be conveyed in the vessel itself, the cargo, or via garbage and cargo residues (e.g. wooden crates, pallets and shoring). The DAWR is responsible for the imposition of Australian border biosecurity arrangements. The Seaports Program, by the former Department of Agriculture (now DAWR), has well developed protocols and procedures applying to vessels arriving in Australia from overseas, including compulsory pre-arrival pratique declarations.
For Skardon River, ship-sourced terrestrial quarantine risks should be considered to be somewhat limited compared to most ports by virtue of the distance from shore that the ships will anchor (approximately 12 km from the mouth of the Skardon River). Noting this, it may be assumed that
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ships arriving at Skardon River from overseas are unlikely to pose an unacceptable level of terrestrial quarantine risks, with these risks appropriately managed by standard DAWR protocols.
Vessels arriving at Skardon River from other Australian ports are unlikely to represent any specific quarantine hazard, assuming that they had already been accorded ‘coastal status’ by Australian quarantine authorities. This will include the domestic movements of barges carrying materials from Cairns and Weipa.
General biofouling and ballast water management requirements are presented below.
Biofouling Management
The National Biofouling Management Guidelines for Commercial Vessels1 provide commercial vessel operators with tools to minimise the amount of biofouling accumulating on their vessels and thereby minimise the risk of spreading marine pests around the Australian coastline. This will include the regular barges proposed to deliver goods and remove wastes from the Project, generally operating between Cairns and/or Weipa, and the site.
All non-trading vessels such as barges, heavy lift vessels and tugs to be used on the Project shall observe the National Biofouling Management Guidelines for Non-Trading Vessels. These vessels will be operating almost exclusively within the Project area, and will have limited opportunity to collect and/or spread any marine pests.
The preferred supplier of marine support services will be required to demonstrate compliance with the relevant requirements of both guidelines.
The OGVs used to export the bauxite are currently not required to implement the guidelines as due to the short timeframes in Australian waters they are considered a low risk. Where a specific biological risk is identified with OGVs they can be placed in quarantine until the risk managed in accordance with current best practice.
Ballast Water Management
Under the Quarantine Act 1908, Australia has implemented stringent regulations regarding the discharge of ballast water in Australian waters. Under the Australian Ballast Water Management Requirements it is prohibited to discharge ballast waters which originate from areas deemed to be of high risk. The DAWR defines all salt water from ports and coastal waters outside Australia’s territorial sea as high risk. Australian Ballast Water Management Requirements prescribe: . High risk ballast waters are prohibited to be discharged in Australian ports or waters; and . Ballast water exchange (if required) can only occur outside Australian waters. Ships entering Australian waters with ballast waters derived from potable water supplies are able to discharge ballasts in Australian ports; however, appropriate supporting documentation is required. The DAWR ensures that foreign ballast water has been managed in accordance with the Australian Ballast Water Management Requirements before permitting its discharge inside Australia’s territorial sea (12 nm limit generally applies). In accordance with the Quarantine Act 1908, OGVs proposing to discharge high risk ballast water will be required to complete their ballast water exchange in mid-ocean outside of Australia’s
1 For complete definitions of commercial and non-trading vessels, refer to the National Biofouling Management Guidelines for Commercial Vessels and National Biofouling Management Guidelines for Non- Trading Vessels, respectively.
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territorial sea (the area within 12 nm of the Australian coastal baseline). Acceptable ballast water exchange methods in deep ocean areas are: . Tanks to be drained until pump suction is lost; . Flow through method with includes pumping three times the volume of the ballast tank; . Compliance regime in agreement with the Australian Ballast Water Management Requirements Version 5; and . Other in-tank treatment agreed with DAWR. Commercial vessels (barges, tugs, support vessels) operating between Australian ports e.g. Cairns/Weipa and the site are considered to be low risk and as such no treatment of ballast water is necessary. Routine Monitoring
Routine marine pest monitoring in the Skardon River will provide early detection of new pest translocations and inform emergency response. It is anticipated that a marine pest monitoring program will be developed and led by Ports North with collaboration from Metro Mining and Gulf Alumina. It is anticipated that the Marine Pest Monitoring Program (MPMP) that will be based on the National System processes, standards and rationale, as described in the Australian Marine Pest Monitoring Manual and Guidelines. The Australian Marine Pest Monitoring Manual details the: . Monitoring design, including sampling procedures and species selection; . Field guides for sampling techniques and collection processes; . Sample handling, preservation and analysis procedures; and . Reporting format, including standard data sheets and reporting forms. The Australian Marine Pest Monitoring Guidelines outlines the: . Decision process for selecting the priority locations and monitoring target species in Australia; . Governance arrangements for the implementation of monitoring programs; . Design pathways and management actions stemming from monitoring results; and . Review process to ensure future improvement to the monitoring programs, the manual and guidelines and the monitoring strategy.
6.8.2 Matters of State Environmental Significance
The Matters of State Environmental Significance (MSES) that are applicable to the Project and as it applies the marine environmental values described are compiled in Table 6-9.
Table 6-9 MSES as they apply to the Bauxite Hills Project Category Description Project applicability Protected area estates Includes all classes of protected area There are no declared protected areas within or (except nature refuges and near the Project area. The nearest area is coordinated conservation areas). Heathlands Resource Reserve approximately 45 km to the east and will not be impacted. Marine Parks Includes state marine park zones. There are no State Marine Park zones declared for the Gulf of Carpentaria. Not applicable.
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Category Description Project applicability Fish habitat areas Includes areas declared as Fish Nearest declared Fish habitat area is Pine River habitat area A, or fish habitat area B Bay in the Weipa area approximately 80 km to under the Fisheries Act 1994. the south. This area is already subject to Also includes protected marine substantial local disturbance. No impacts plants. expected from the Project activities. The Project will require some clearing of protected marine plants. These matters are treated in Chapter 4 – Terrestrial and Aquatic Ecology. Threatened Species Includes flora and fauna species There are several terrestrial fauna and flora listed as Special Least Concern, species listed as Endangered, Vulnerable or Vulnerable, or Endangered under the Special Least Concern (including bird species NC Act and includes habitat that listed as Migratory under the EPBC Act) that supports a listed fauna species (e.g. occur or have potential to occur in the study foraging roosting or breeding area. These species are treated in Chapter 5 – habitat). Terrestrial and Aquatic Ecology and Chapter 7 – MNES. There are nine marine fauna species listed as Endangered or Vulnerable under the NC Act that have potential to occur in the study area. Refer Section 6.5.4. Regulated vegetation Includes: There are REs classified as Of Concern, and REs classified as ‘endangered’ or ‘of regulated vegetation intersecting a watercourse concern’, that may be impacted by the Project. These matters are treated in Chapter 5 – Terrestrial and ‘High value regrowth’ areas Aquatic Ecology. containing ‘endangered’ or ‘of concern’ REs; and REs classified as ‘watercourse’. Wild rivers (high Include the ‘high preservation area’ At the time of writing the wild rivers legislation preservation areas) in the wild river declaration for the has been repealed and therefore does not apply. area. High conservation value Includes: There are wetland areas considered as of ‘High wetlands Wetlands assessed as ‘High Ecological Significance’ that may be impacted by Ecological Significance’ on the map of the Project. These matters are treated in Chapter referable wetlands; or 5 – Terrestrial and Aquatic Ecology. High ecological value freshwater and estuarine areas declared under the Environmental Protection (water) Policy 2009. Legally secured offset Includes offset areas legally secured There are no secured offset areas on or near the areas under a registered covenant, Project area. Not applicable. easement, conservation agreement or development approval condition.
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6.8.2.1 Habitat for Endangered or Vulnerable Marine Fauna
Section 6.5.4 describes the likelihood of occurrence of threatened (listed under the NC Act and EPBC Act) marine fauna. Species that are considered unlikely to occur will not experience significant residual impacts from the Project activities. There are two marine fauna species listed as Endangered under the NC Act which are considered as likely to occur in the study area waters:
. Loggerhead Turtle (also listed as Endangered under the EPBC Act); and
. Olive Ridley Turtle (also listed as Endangered under the EPBC Act).
There are seven marine fauna species listed as Vulnerable under the NC Act which are considered as likely or known to occur in the study area waters:
. Estuarine Crocodile (also listed as Migratory under the EPBC Act);
. Flatback Turtle (also listed as Vulnerable under the EPBC Act);
. Green Turtle (also listed as Vulnerable under the EPBC Act);
. Hawksbill Turtle (also listed as Vulnerable under the EPBC Act);
. Dugong (also listed as Migratory under the EPBC Act);
. Indo-Pacific Humpback Dolphin (also listed as Migratory under the EPBC Act); and
. Australian Snubfin Dolphin (also listed as Migratory under the EPBC Act).
A further five fish species listed only under the EPBC Act are also considered to have some potential to occur:
. Speartooth Shark (Critically Endangered);
. Largetooth Sawfish (Vulnerable);
. Dwarf Sawfish (Vulnerable);
. Green Sawfish (Vulnerable);
. Narrow Sawfish (Migratory); and
. Coastal Manta Ray (Migratory).
Under the Queensland Environmental Offsets Policy V1.1 (SoQ, 2014a) State and local governments can only impose an offset condition in relation to a prescribed activity, if the same, or substantially the same impact and the same, or substantially the same matter has not been subject to assessment under “the Environment Protection and Biodiversity Conservation Act 1999, to the extent the assessment relates to an activity that has been declared a ‘controlled action’ by the Commonwealth Minister.”
The Project was subject to a referral to DotE and was declared a controlled action in September 2015. On this basis the following significant impact assessments for threatened marine species are based on the Matters of National Environmental Significance (MNES), Significant Impact Guidelines 1.1 (DotE, 2013) (refer Chapter 7 – MNES). It is noted the significant impact criteria for NC Act-listed fauna species listed in the Significant Residual Impact Guideline (SoQ, 2014b) are very similar to the
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MNES impact criteria, excepting Migratory species which are not considered under the MSES guidelines.
The MNES significant impact criteria assessment for each of the marine fauna species listed above is presented in the following tables and in Chapter 7 – MNES.
Marine Turtles
Existing Threats
Outside the Project development processes there are two major anthropogenic threats to marine turtles along the beaches of western Cape York – predation by feral pigs and entanglement in discarded high seas fishing net (ghost nets). The former is considered the most significant. Feral pigs are a well acknowledged environmental problem in Australia and they are identified as key threatening process under the EPBC Act 1999 and a Threat Abatement Plan (TAP) is currently in place. Impacts on Flatback and Hawksbill Turtle nesting is identified specifically as a significant reason for listing feral pigs as a key threatening process. Feral pigs and cattle have been identified within the coastal zone adjacent to the Skardon River entrance and along the river system within and adjacent to the bauxite plateau (Tom Koskela, Pers. Comm). Evidence of pig damage to turtle nests (tracks and fresh rooting marks) have been observed by PaCE along the northern and southern shores along the entrance to the Skardon River.
Ghost nets are discarded or lost nets that continue to float around the ocean until eventually they wash up on beaches. These nests can entangle and kill marine turtles in the open ocean and/or in inshore areas. According to the Carpentaria Ghost Nets Program which is an Indigenous community and Commonwealth government partnership in northern Australia, most ghost nets in the Gulf of Carpentaria originate from south-east Asian countries in particular Taiwan, Indonesia and Korea.
Significant Impact Assessment
Flatback Turtles are well known to commonly nest along beaches both south and north of the mouth of the Skardon River (refer Table 6-7). Olive Ridley Turtle is also known to nest in low densities on western Cape York Peninsula south to Weipa (Limpus 2007). All marine turtle species (except Leatherback Turtle) are considered to have some potential to occur in the wider area. The proposed BLF have recorded seagrass beds within its immediate vicinity which may provide foraging habitat for Green Turtle. However, these are low-density and relatively small in extent and considered unlikely to support a population of the species.
The proposed construction and operations of the Project present a limited impact to marine turtles. Disturbance to preferred foraging and nesting habitat is negligible given the absence of dredging or excavation, and the potential impacts attributable to lighting are not considered a significant issue given the distance between the nesting beaches and proposed barge facility options within the upper reaches of the Skardon River. Increased vessel movements within the Skardon River and adjacent coastal regions present the greatest potential for interaction, though the risks are considered minor. Marine Turtles are considered separately in each of the following tables.
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Table 6-10 Assessment against significant impact criteria: Flatback Turtle Criterion Assessment Against Significance Criteria (Vulnerable) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of an important decrease in the size of the Flatback Turtle population. population of the species Reduce the area of The Flatback Turtle has an extremely large area of occupancy and the Project will occupancy of an important not plausibly reduce this area of occupancy in any meaningful or measurable way. population Fragment an existing The Project contains no components that could plausibly fragment the existing important population into populations of Flatback Turtles. two or more populations Adversely affect habitat The Project will not remove that is potentially used as foraging habitat by Flatback critical to the survival of the Turtles. The nearest recognised important breeding habitat or BIA is situated at species Crab Island some 85 km to the north. However, Flatback Turtles are known to nest along the Skardon River beaches. The key threat to nesting habitat is the presence of feral pigs. Activities to mitigate the effects of feral pigs in the wider area by Metro Mining, or others, will provide significant respite in nesting conditions and recruitment success. Disrupt the breeding cycle of Lighting has the potential to disrupt the nesting activities of marine turtles. The an important population mining operations are sufficiently inland (approx. 10 km) away from beach nesting areas and buffered by extensive native vegetation to the extent that light spill from mining operations is highly unlikely to be an impacting process. The nesting beaches themselves will not be traversed during construction or operation of the mine. The light from the Project will interact with other light sources from the adjacent SRBP, however given the distance of the Projects from potential nesting areas (> 6 km at their nearest) cumulative impacts are not expected. A contingency plan to reduce light spill will be included as part of the Project’s EMP should it be deemed necessary. Modify, destroy, remove, The Project will not modify, destroy, isolate or decrease the quality of the habitat to isolate or decrease the the extent that any decline in the species will occur. Predicted benthic impacts to availability or quality of seagrass and biota within the channel alignment will be locally insignificant. habitat to the extent that the species is likely to decline Result in invasive species that Port projects including those of a larger scale, and in areas adjacent to nesting areas are harmful to a vulnerable (e.g. central Queensland), have not been implicated in the introduction of invasive species becoming established species that are harmful to the species. Ballast water of vessels in bulk carriers will in the vulnerable species adhere to relevant national and international standards aimed at preventing the habitat spread of invasive species. Barges proposed for use are designed to operate with minimum ballast and where ballast is required locally sourced water will be used thus eliminating the risk of introduction or translocation of invasive species. Introduce disease that may Port projects including those of a larger scale, and in areas adjacent to nesting areas cause the species to decline where the abundance of Flatback Turtles is relatively high (e.g. central Queensland), have not been implicated in the introduction of disease. The Project will not plausibly introduce disease that may cause the population of Flatback Turtles to decline. Interfere substantially with The nature and scale of the Project will not plausibly interfere with the recovery of the recovery of the species the species as outlined in the national Marine Turtle Recovery Plan. The proposed implementation of feral animal control and marine debris clean-up program will assist recovery potential for the region.
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Table 6-11 Assessment against significant impact criteria: Green Turtle Criterion Assessment Against Significance Criteria (Vulnerable) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of an important decrease in the size of the Green Turtle population. population of the species Reduce the area of The Green Turtle has an extremely large (circumglobal) area of occupancy and the occupancy of an important Project will not plausibly reduce this area of occupancy in any meaningful or population measurable way. Fragment an existing The Project contains no components that could plausibly fragment the existing important population into populations of Green Turtles. two or more populations Adversely affect habitat Based on the current state of knowledge, no BIA has been identified for the Green critical to the survival of the Turtle at or adjacent to the proposed Project location. species Disrupt the breeding cycle of There is no nesting of Green Turtles in the region. an important population Modify, destroy, remove, High quality habitat (seagrass) for Green Turtles is absent at and adjacent to the isolate or decrease the proposed Project location. The area is to be modified (but not removed) by the availability or quality of construction of BLF. The available seagrasses do not constitute important foraging habitat to the extent that the habitat for Green Turtles. species is likely to decline Result in invasive species that Port projects including those of a larger scale, and in areas adjacent to nesting areas are harmful to a vulnerable (e.g. central Queensland), have not been implicated in the introduction of invasive species becoming established species that are harmful to the species. Ballast water of vessels in bulk carriers will in the vulnerable species adhere to relevant national and international standards aimed at preventing the habitat spread of invasive species. Barges proposed for use are designed to operate with minimum ballast and where ballast is required locally sourced water will be used thus eliminating the risk of introduction or translocation of invasive species. Introduce disease that may Port projects including those of a larger scale, and in areas adjacent to nesting areas cause the species to decline (e.g. central Queensland), have not been implicated in the introduction of disease harmful to the species. Ballast water of vessels in bulk carriers will adhere to relevant national and international standards aimed at preventing the spread of invasive species (including disease). Interfere substantially with The nature and scale of the Project will not plausibly interfere with the recovery of the recovery of the species the species as outlined in the national Marine Turtle Recovery Plan.
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Table 6-12 Assessment against significant impact criteria: Hawksbill Turtle Criterion Assessment Against Significance Criteria (Vulnerable) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of an important decrease in the size of the Hawksbill Turtle population. population of the species Reduce the area of The Hawksbill Turtle has an extremely large area of occupancy and the Project will occupancy of an important not plausibly reduce this area of occupancy in any meaningful or measurable way. population Fragment an existing The Project contains no components that could plausibly fragment the existing important population into populations of Hawksbill Turtles. two or more populations Adversely affect habitat Based on the current state of knowledge, the nearest BIAs has been identified north critical to the survival of the of the Cotterell River, approximately 40km to the north of the Skardon River. They species are omnivorous and are believed to feed predominantly on algae, sponges and seagrass over coral reef areas. The nearest coral reef structure to the Project is located 6-7 km south of the Skardon River. Additional reef habitat is located at Kerr Reef, 15 km to the south west. Disrupt the breeding cycle of Lighting has the potential to disrupt the nesting activities of marine turtles. The an important population mining operations are sufficiently inland (approx.. 10 km) away from beach nesting areas and buffered by extensive native vegetation to the extent that light spill from mining operations is highly unlikely to be an impacting process. The nesting beaches themselves will not be traversed during construction or operation of the mine. Staff or contractors will not be permitted to camp on beaches (check that this is the case). The light from the proposed Project will not be interacting with any other light sources in the region to create a cumulative impact. A contingency plan to reduce light spill will be included as part of the Project’s EMP should it be deemed necessary. Modify, destroy, remove, The Project will not modify, destroy or decrease habitat through that is potentially isolate or decrease the used as foraging by Hawksbill Turtles. Given the available foraging area for the availability or quality of species in the Gulf of Carpentaria, the nature and scale of the disturbance will not habitat to the extent that the isolate or decrease the quality of the habitat to the extent that any decline in the species is likely to decline species will occur. Result in invasive species that Port projects including those of a larger scale, have not been implicated in the are harmful to a vulnerable introduction of invasive species that are harmful to the species. Ballast water of species becoming established vessels in bulk carriers will adhere to relevant national and international standards in the vulnerable species aimed at preventing the spread of invasive species. Barges proposed for use are habitat designed to operate with minimum ballast and where ballast is required locally sourced water will be used thus eliminating the risk of introduction or translocation of invasive species. Introduce disease that may Port projects including those of a larger scale, and in areas adjacent to nesting areas cause the species to decline have not been implicated in the introduction of disease harmful to the species. Ballast water of vessels in bulk carriers will adhere to relevant national and international standards aimed at preventing the spread of invasive species (including disease). Interfere substantially with The nature and scale of the Project will not plausibly interfere with the recovery of the recovery of the species the species as outlined in the national Marine Turtle Recovery Plan. The proposed implementation of feral animal control and marine debris clean-up program will assist recovery potential for the region.
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Table 6-13 Assessment against significant impact criteria: Loggerhead Turtle Criterion Assessment Against Significance Criteria (Endangered) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of a population of decrease in the size of a population. the species Reduce the area of The Loggerhead Turtle has a global distribution throughout tropical, sub-tropical and occupancy of the species temperate waters. The spatial scale of the Project is insignificant with respect to the area of occupancy of the species. Fragment an existing The proposed activity does not feasibly create a barrier to movement either directly population into two or more or indirectly. populations Adversely affect habitat Based on the current state of knowledge, no BIA has been identified for the critical to the survival of the Loggerhead Turtle at or adjacent to the proposed Project location. species Disrupt the breeding cycle of There is no nesting of loggerhead turtles in the region. a population Modify, destroy, remove, The Project will not modify, destroy. Isolate or decrease the quality of the habitat to isolate or decrease the the extent that any decline in the species will occur. availability or quality of habitat to the extent that the species is likely to decline Result in invasive species that Port projects including those of a larger scale, and in areas adjacent to nesting areas are harmful to a vulnerable where the abundance of loggerhead turtles is relatively high (e.g. central species becoming established Queensland), have not been implicated in the introduction of invasive species that are in the endangered species harmful to the species. Ballast water of vessels in bulk carriers will adhere to relevant habitat national and international standards aimed at preventing the spread of invasive species. Barges proposed for use are designed to operate with minimum ballast and where ballast is required locally sourced water will be used thus eliminating the risk of introduction or translocation of invasive species. Introduce disease that may Port projects including those of a larger scale, and in areas adjacent to nesting areas cause the species to decline have not been implicated in the introduction of disease harmful to the species. Ballast water of vessels in bulk carriers will adhere to relevant national and international standards aimed at preventing the spread of invasive species (including disease). Interfere with the recovery of The nature and scale of the Project will not plausibly interfere with the recovery of the species the species as outlined in the national Marine Turtle Recovery Plan.
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Table 6-14 Assessment against significant impact criteria: Olive Ridley Turtle Criterion Assessment Against Significance Criteria (Endangered) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of a population of decrease in the size of a population. the species Reduce the area of The Olive Ridley turtle has a circumtropical distribution throughout tropical, sub- occupancy of the species tropical and temperate waters. The spatial scale of the Project is insignificant with respect to the area of occupancy of the species. Fragment an existing The proposed activity does not feasibly create a barrier to movement either directly population into two or more or indirectly. populations Adversely affect habitat Based on the current state of knowledge, no BIA has been identified for the Olive critical to the survival of the Ridley Turtle at or adjacent to the proposed Project location. species Disrupt the breeding cycle of Lighting has the potential to disrupt the nesting activities of marine turtles. The a population mining operations are sufficiently inland (approx. 10 km) away from beach nesting areas and buffered by extensive native vegetation to the extent that light spill from mining operations will not be an impacting process. The nesting beaches themselves will not be traversed during construction or operation of the mine. Staff or contractors will not be permitted to camp on beaches (check that this is the case). The light from the proposed Project will not be interacting with any other light sources in the region to create a cumulative impact. A contingency plan to reduce light spill will be included as part of the Project’s EMP should it be deemed necessary. Modify, destroy, remove, The Project will not modify, remove or destroy habitat that is potentially used as isolate or decrease the foraging by Olive Ridley Turtles. availability or quality of habitat to the extent that the species is likely to decline Result in invasive species that Port developments at Weipa have not been implicated in the introduction of invasive are harmful to a vulnerable species, and these developments are at a larger scale than that proposed for the species becoming established Project. Ballast water of vessels in bulk carriers will adhere to relevant national and in the endangered species international standards aimed at preventing the spread of invasive species. Barges habitat proposed for use are designed to operate with minimum ballast and where ballast is required locally sourced water will be used thus eliminating the risk of introduction or translocation of invasive species Introduce disease that may Port developments at Weipa have not been implicated in the introduction of disease, cause the species to decline and these developments are at a larger scale than that proposed for the Bauxite Hills Project. Ballast water of vessels in bulk carriers will adhere to relevant national and international standards aimed at preventing the spread of invasive species (and diseases). The Project will not plausibly introduce disease that may cause the population of Olive Ridley Turtles to decline. Interfere with the recovery of The nature and scale of the Project will not plausibly interfere with the recovery of the species the species as outlined in the national Marine Turtle Recovery Plan. The proposed implementation of feral animal control and marine debris clean-up program will assist recovery potential for the region.
Sawfish Species and Speartooth Shark
It is considered likely that three species of sawfish – the Narrow sawfish, Largetooth Sawfish and the Dwarf Sawfish may occur within the Skardon River. A further species, the Green Sawfish may occur at the proposed transhipping location. Based on existing survey evidence a key location for the Speartooth Shark and several of the sawfish is the nearby Port Musgrave/Ducie River/Wenlock River area, directly to the south of the Skardon River.
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While not confirmed as occurring in the Skardon River, it is plausible that the Speartooth Shark also occurs there. However, the catchment of the Skardon River is small and is supplied with only minor freshwater flows during the dry season. The life history of Speartooth Shark pups indicate they move into the upper estuary adjacent to freshwater flows with lower salinity regimes. If flows in the Skardon River are not sufficient (given their small size), then the river may not be suitable to sustain this strategy for the estimated three to six years before migration to more saline waters occurs.
Given the lack of presence/absence data of the four Sawfish species and the Speartooth Shark in the Skardon River, Metro Mining has adopted a precautionary approach managing potential impacts and will assume that all four species of Sawfish and the Speartooth Shark are highly likely to be present in the Skardon River.
The significant overall threat to sawfishes and the Speartooth Shark is very clearly associated with incidental capture by commercial fishing operations. A lesser impact is from recreational fishing activities. The impacting processes from the proposed Project are highly unlikely to result in impacts to sawfishes or the Speartooth Shark. The species will not plausibly be negatively impacted by artificial lighting, underwater noise or shipping movements. Proposed construction and operational activities are outside the wet season which is identified as the key pupping period for sawfishes. Proposed construction and operational activities also largely occur outside of what is believed to be the pupping period for the Speartooth Shark. The barge transit routes or the transhipping operations will not alter key habitat. The Project will not directly or indirectly alter the hydrology of the Skardon River and as such will not affect the extent or condition of freshwater and brackish water habitats that are considered to be important for the life history of Largetooth Sawfish and the Speartooth Shark.
The placement of the piling at the proposed barge landing location, may create a local habitat that is not utilised by Largetooth Sawfish, but this habitat modification does not provide a barrier to movement of animals up and down the river as they do not extend across the whole river. The area to be disturbed is not consequential given the area of the Skardon River and highly unlikely to have any impact on Largetooth Sawfish at the population level. The assessment in Table 6-15 demonstrates the Project will not comprise impacts to the extent that recovery of sawfishes and river sharks will be negatively affected should they occur in the Skardon River. Table 6-22 assesses the impacts to Narrow Sawfish using the MNES guidelines for migratory species.
Table 6-15 Assessment against significant impact criteria: three sawfish species and Speartooth Shark Criterion Assessment Against Significance Criteria (Endangered) Lead to a long-term decrease The Project is highly unlikely to lead to a long term decrease in the size of any in the size of a population populations of Sawfish or Speartooth Shark. The proposed Project will not plausibly result in the death of any individual animals, and the impacting processes are not of a type or scale where a long-term decrease in the size of the population is plausible. Fisheries impact are widely considered the key impacting factors influencing populations. Reduce the area of The Skardon River is not currently included as part of the published estimate of the occupancy of the species area of occupancy of the Speartooth Shark (Stevens et al., 2005). If the species does occur there, the estimated area of occupancy for the species will increase. The impacting processes that will occur as a result of the proposed Project will not feasibly reduce the area of occupancy. The area of occupancy for the Largetooth and Green Sawfishes is northern Australian waters (north of 20° S). The Dwarf Sawfish has an area of occupancy from the Gulf of Carpentaria and then across northern Australia and down into the Pilbara region of Western Australia. The Project will not feasibly reduce the area of occupancy of sawfishes. Fragment an existing The proposed activity does not feasibly create a barrier to the movement or population into two or more migration of sawfish or the Speartooth Shark - either directly or indirectly. populations
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Criterion Assessment Against Significance Criteria (Endangered) Adversely affect habitat The critical habitat for the survival of the Speartooth Shark on western Cape York is critical to the survival of the the Port Musgrave/Ducie River/Wenlock system which is remote from the proposed species Project and not impacted by it. Critical habitat for the Largetooth Sawfish are the freshwater areas (including isolated pools) which the species likely uses as a nursery area. Freshwater habitat is also considered important nursery habitat for Speartooth Sharks. This critical habitat will not be impacted directly or indirectly by the proposed Project. Available information suggests Dwarf Sawfish use mangrove habitat and shallow waters adjacent to mangroves and such habitat will not be altered to any significant extent by the proposed Project with approximately 20.5 ha of mangroves expected to be cleared. Available information suggests that the Green Sawfish prefers the sand and mud flats outside of river mouths, although it does extend into deeper coastal waters. The transhipping operations will not alter habitat such as the shallow sand and mud banks that the Green Sawfish prefers. Disrupt the breeding cycle of The Project is highly unlikely to disrupt the breeding cycle for sawfish or the an important population Speartooth Shark. For sawfish, pupping occurs during the wet season when construction and operational activities will not occur. To the best available knowledge pupping for the Speartooth Shark occurs October- December. Construction is not proposed during this period. Operations will not plausibly interfere with the passage of Speartooth Shark for pupping in the lower estuary, or the migration of recruits to the upper estuarine/lower freshwater reaches if they do occur. Modify, destroy, remove, The Project will modify (but not remove) habitat through the placement of pilings at isolate or decrease the the BLF. The nature, scale and location of these habitat modifications will not availability or quality of plausibly result in the decline of sawfishes or the Speartooth Shark. The installation habitat to the extent that the of culverts between the freshwater and estuarine reaches will improve hydrological species is likely to decline flows of the area. Connectivity between the freshwater and marine system will remain. Result in invasive species that Port developments at Weipa have not been implicated in the introduction of invasive are harmful to a vulnerable species, and these developments are at a larger scale than that proposed for the SRBP. species becoming established Ballast water of vessels in bulk carriers will adhere to relevant national and in the vulnerable species international standards aimed at preventing the spread of invasive species. Barges habitat proposed for use are designed to operate with minimum ballast and where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Introduce disease that may Port developments at Weipa have not been implicated in the introduction of disease, cause the species to decline and these developments are at a larger scale than that proposed for the SRBP. Ballast water of vessels in bulk carriers will adhere to relevant national and international standards aimed at preventing the spread of invasive species. Barges proposed for use are designed to operate with minimum ballast and where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Interfere substantially with The nature and scale of the Project will not plausibly interfere with the recovery of the recovery of the species the species. The proposed Project can contribute positively to recovery through active education of staff and contractors of the conservation status and threats to sawfishes and the Speartooth Shark. Bans on fishing and providing consideration to funding research within the study area will contribute to the overall management objectives of the draft recovery plan.
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Table 6-16 Assessment against significant impact criteria: Narrow Sawfish Criterion Assessment Against Significance Criteria (Migratory) Migratory Species Substantially modify, destroy The Narrow sawfish is broadly distributed throughout the Gulf of Carpentaria and uses or isolate an area of the full range of coastal habitat, from estuary to nearshore offshore waters to a depth important habitat for a of 40 m. The Project operations will not substantially modify or impact upon important migratory species habitat. Given known distributions of the Narrow Sawfish within the Queensland Gulf waters (approx. 90,000 km2), the proposed works will, at an absolute maximum, (1,000 km2) represent low intensity utilisation of less than 0.01% of the habitat area. Result in an invasive species Port developments at Weipa have not been implicated in the introduction of invasive that is harmful to the species, and these developments are at a larger scale than that proposed for the migratory species becoming Project. Ballast water of vessels in bulk carriers will adhere to relevant national and established in an area of international standards aimed at preventing the spread of invasive species. Barges important habitat for the proposed for use are designed to operate with minimum ballast and where ballast is migratory species required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Seriously disrupt the lifecycle Given the identified distribution of the species within the Gulf it is highly unlikely that (breeding, feeding, migration the localised passage of barges within the Skardon River and adjacent waters will or resting behaviour) of an seriously impact upon breeding, feeding or resting behaviour of a significant portion ecologically significant of the population. The fecundity of the Narrow sawfish makes it considerably less proportion of the population sensitive to pressures potentially experienced by other sawfish and migratory species. of a migratory species
Estuarine Crocodile
Crocodiles are a common resident of the Skardon River with bank slides and individuals being observed within the estuary system of the Skardon River on numerous occasions (Tom Koskela, pers. Comm.) including during surveys for the SRBP (RPS, 2015). Overall, the Project will not significantly impact the estuarine crocodile. Crocodiles exist in close proximity to human habitation and port operations throughout Queensland. The Skardon River has not been identified as a key area for nesting. The Port Musgrave area, and in particular, the Wenlock River, is recognised as containing significant habitat for the estuarine crocodiles with one of the largest breeding populations in Queensland.
Table 6-17 Assessment against significant impact criteria: Estuarine Crocodile Criterion Assessment Against Significance Criteria (Migratory) Migratory Species Substantially modify, destroy While Estuarine Crocodiles utilise the Skardon River, the proposed Project, the barge or isolate an area of landing location cannot be considered important habitat. The scale of habitat important habitat for a modification at the barge landing location (clearing of 20.5 ha of mangroves) is not migratory species sufficient to alter the carrying capacity of the habitat to the extent that river wide populations of the Estuarine Crocodile will be impacted. The critical habitat for the Estuarine Crocodile is the Wenlock River which is not impacted by the Project. Result in an invasive species Port developments at Weipa have not been implicated in the introduction of invasive that is harmful to the species, and these developments are at a larger scale than that proposed for the migratory species becoming Bauxite Hills Project. Ballast water of vessels in bulk carriers will adhere to relevant established in an area of national and international standards aimed at preventing the spread of invasive important habitat for the species. Barges proposed for use are designed to operate with minimum ballast and migratory species where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated.
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Seriously disrupt the lifecycle (breeding, feeding, migration The construction and operation of the Project is largely outside of the breeding season or resting behaviour) of an for the estuarine crocodile. The Project contains no aspects that will create a barrier ecologically significant to the movement of the Estuarine Crocodile or alter the foraging of a key population. proportion of the population The port construction and operations are in the marine environment. of a migratory species
Dugong
The species has been recorded in Skardon River only once previously during seagrass surveys (Roelofs, 2003). The proposed BLF have recorded seagrass within its immediate vicinity as well as other scattered areas in the Skardon River. It is unlikely the extent of seagrass in the river constitutes a sufficient biomass to sustain a population of Dugong. Given the occurrence of Dugong within heavy industry Ports such as Gladstone Harbour, and busy coastal waterways of Moreton Bay and Cleveland Bay, the severity of any Project affects are likely to be low.
Table 6-18 Assessment against significant impact criteria: Dugong Criterion Assessment Migratory Species Substantially modify, destroy The extent of seagrass habitat in the Skardon River is unlikely to be sufficient to or isolate an area of support Dugong populations. The habitat impacts that will result from the Project will important habitat for a not destroy or isolate an area of important dugong habitat. migratory species Result in an invasive species Port developments at Weipa have not been implicated in the introduction of invasive that is harmful to the species, and these developments are at a larger scale than that proposed for the migratory species becoming Bauxite Hills Project. Ballast water of vessels in bulk carriers will adhere to relevant established in an area of national and international standards aimed at preventing the spread of invasive important habitat for the species. Barges proposed for use are designed to operate with minimum ballast and migratory species where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Seriously disrupt the lifecycle (breeding, feeding, migration The Project is not in a location that contains habitat suitable to support an ecologically or resting behaviour) of an significant dugong population. As such, there is little or no scope for the Project to ecologically significant serious disrupt the species lifecycle. proportion of the population of a migratory species
Indo-Pacific Humpback Dolphin and Australian Snubfin Dolphin
Australian Snubfin Dolphin has been recorded in the Skardon River estuary and adjacent open water habitat in recent years (Table 6-8). Indo-Pacific Humpback Dolphin has been observed in the Port Musgrave region and is considered likely to occur. Dolphin species may be impacted by increased underwater noise and vessel movements as a result of the Project activities. However, dolphins co- exist at a large number of locations on the Queensland east coast at, or directly adjacent to port facilities where vessel movements are substantially greater than proposed for the Project. This provides an indication that animals can adapt to this disturbance and maintain viable populations. Overall with respect to cetaceans, it is concluded that the Project is unlikely to have a significant impact (Table 6-15). While no significant impact criteria exist for cetacean species under the EPBC Act, this assessment has taken a precautionary approach and utilised those applicable to endangered species and very similar to the criteria for Matters of State Environmental Significance used for threatened species listed under the NC Act (such as Australian Snubfin Dolphin and Indo- Pacific Humpback Dolphin).
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Table 6-19 Assessment against significant impact criteria: Australian Snubfin Dolphin and Indo-Pacific Humpback Dolphin Criterion Assessment Against Significance Criteria (Migratory) Lead to a long-term decrease The Project is not of a nature or scale that could plausibly lead to a long term in the size of a population of decrease in the size of a population. the species Reduce the area of There are uncertainties regarding the area of occupancy in the Gulf of Carpentaria of occupancy of the species the dolphin species. However, there is no available information which identifies that the proposed Project location is an important area for dolphins. The scale of the Project is small relative to available habitat that may be occupied by the species. Fragment an existing The proposed activity does not feasibly create a barrier to movement either directly population into two or more or indirectly. The available information from areas including Cleveland Bay and populations Moreton Bay where port developments are extensive and vessel movements are substantial, demonstrate that populations do not fragment in response to this type of disturbance, even when it is of a scale and intensity much greater than proposed in this Project. Adversely affect habitat Based on the current state of knowledge, no BIAs have been identified for the dolphin critical to the survival of the species at or adjacent to the proposed Project location. species Disrupt the breeding cycle of There is highly unlikely to disrupt the breeding cycle for the dolphin species a population considered. Modify, destroy, remove, The Project will potentially modify (but not remove) habitat through vessel anchorage isolate or decrease the that is potentially used as foraging habitat by dolphin species. This habitat though is availability or quality of not critical habitat. habitat to the extent that the species is likely to decline Result in invasive species that Port developments at Weipa have not been implicated in the introduction of invasive are harmful to a vulnerable species, and these developments are at a larger scale than that proposed for the species becoming established Project. Ballast water of vessels in bulk carriers will adhere to relevant national and in the endangered species international standards aimed at preventing the spread of invasive species. Barges habitat proposed for use are designed to operate with minimum ballast and where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Introduce disease that may Port developments at Weipa have not been implicated in the introduction of disease, cause the species to decline and these developments are at a larger scale than that proposed for the Project. Given the proposed controls managing ballast water, the Project will not plausibly introduce disease that may cause the population of dolphin species to decline. Interfere with the recovery of The nature and scale of the Project will not plausibly interfere with the recovery of the the species species.
Reef Manta Ray
As the Australian populations are currently unaffected by significant pressures of fishing take or on habitat, the listing within the EPBC Act under migratory species seeks to provide legislative protection to contribute to mitigating threats in other parts of the world. Experts consulted as part of the application for listing in Australia agree that the Australian population, based on current evidence, is currently one of the world’s healthiest (Department of Environment, 2012). While the concept of preserving a species globally by listing it locally provides some formal system of protection, the proposed operations by Metro Mining do not represent significant threats to its sustainability locally, nationally or internationally.
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Table 6-20 Assessment against significant impact criteria: Coastal Manta Ray Criterion Assessment Migratory Species Substantially modify, destroy Key aggregation sites for Reef Manta Ray are located along the eastern coast and or isolate an area of north west coast of Australia. These sites represent important sites for breeding, important habitat for a feeding and cleaning. The Project will not have an impact upon reef habitat or alter migratory species hydrological connectivity. The Project will not conceivably alter nutrient regimes in the Gulf of Carpentaria or alter food sources via changing plankton abundance or distribution. Result in an invasive species Port developments at Weipa have not been implicated in the introduction of invasive that is harmful to the species, and these developments are at a larger scale than that proposed for the migratory species becoming Bauxite Hills Project. Ballast water of vessels in bulk carriers will adhere to relevant established in an area of national and international standards aimed at preventing the spread of invasive important habitat for the species. Barges proposed for use are designed to operate with minimum ballast and migratory species where ballast is required fresh water will be used thus eliminating the risk of introduction or translocation of invasive species. In an exceptional circumstance where marine water was required for barge ballast, it will be retained onboard for the minimum time to ensure risk was negated. Seriously disrupt the lifecycle The study area is outside the identified areas for aggregation in Australia. Given the (breeding, feeding, migration published significance of these aggregation areas to the species, serious disruption or resting behaviour) of an upon breeding, feeding or resting are not plausible. The Project will not establish ecologically significant barriers to migration. Some interaction with vessel movements during Project proportion of the population operations may be plausible, though given the nature of this species, such interactions of a migratory species will not appear detrimental to populations (the eastern coast and west coast populations support tourism ventures where recreational divers swim with aggregating Manta Rays). 6.9 Qualitative Risk Assessment
A qualitative risk assessment of potential impacts to the marine flora and fauna are summarised in Table 6-21. An analysis of initial risk, without mitigation, was considered in relation to the marine environment. The residual risk considers the mitigation and management measures developed for this element and put forward in this assessment.
Table 6-21 Qualitative risk assessment - marine ecology
Management and Mitigation Potential Impacts
sequence Measures
Initial Initial Initial
Likelihood Risk Initial
Residual Risk Residual
Con
. ASS and PASS disturbance minimised during operations; . Consideration of further ASS testing Acid sulfate soil Minor Unlikely Low on finalised Project footprint; and Low disturbance . Management and treatment plans developed if ASS or PASS is to be disturbed. . Vessel speeds reduced as low as practicable within estuary; Changed behaviours as a . Unnecessary ship movements result of marine noise Minor Possible Medium avoided; and Low and vibration during operation . Shallow water habitats avoided and vessel management plan implemented.
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Management and Mitigation Potential Impacts
sequence
Initial Initial Initial Measures
Likelihood Risk Initial
Residual Risk Residual
Con
. Conduct seagrass surveys pre- construction when construction footprint is finalised; . Implement appropriate vegetation monitoring programs including long- term biannual seagrass monitoring program for the Skardon River; . Minimise required clearing and limit access over seagrass habitats; . Minimise adjacent seagrass damage during construction by managing the Marine habitat Almost Minor High buffer around the development; Medium disturbance Certain . Restrict unnecessary access to saltmarsh and mangrove habitats; . Clearing activities subject to offset program; . During construction consider deployment of ‘silt curtains’ to screen off known habitat areas (seagrass) from intermittent passage of sediment plumes; and . Fauna spotter used during construction. . Exclusion of fishing at Metro Mining controlled premises; . Vessel exclusion zones over shallow Physical interaction with water; fauna species during . Set speed limits for vessel construction and movements in estuary; operations Minor Possible Medium . Significant Species Management plan Low (Speartooth Shark, implemented including staff sawfish, Dugong, education; dolphin, marine turtles) . Exclusion of site personnel from beaches adjacent to Skardon River; and . Noise abatement.
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Management and Mitigation Potential Impacts
sequence
Initial Initial Initial Measures
Likelihood Risk Initial
Residual Risk Residual
Con
. Piling operations to be carried out during the day only; . Safety zone to be established at 1000 m prior to piling activity; . Trained marine fauna observer to inspect area for 30 minutes prior to start; . Soft startup of piling operations; Changed behaviours as a . Shut-down procedure in place during result of marine noise Moderate Unlikely Medium construction in the event marine Low and vibration during construction fauna is sighted during construction activity; . Unnecessary ship movements avoided; . Vessel speeds reduced as slow as practicable; and . Shallow water habitats avoided and vessel management plan implemented. . Minimise vessel speed to as low as Vessel movements – bow practicable to minimise prop wash wave impacts causing Moderate Unlikely Medium and bank erosion; and Low shore erosion . Remain within the deep water navigation channels during transit. . Establish ambient water quality monitoring program prior to construction; . Establish annual hydrographic surveys of the channel offshore of the mouth of the Skardon River; Propeller wash causing . Minimise vessel speed to as low as increase in ambient practicable; Insignificant Possible Low Low turbidity and damage to . Vessel operations to control vessel benthos movement to minimise propeller wash by targeting upper tidal range for barge movements; . Limit passage over or immediately adjacent to seagrass habitats; and . Utilise defined shipping routes and follow proposed vessel access plan. . Detailed preclearance survey to ensure higher density habitats are avoided; Bulk carrier anchorage . Shipping schedules planned to damage to benthic Minor Possible Medium Low minimise vessel time at anchor; and communities . Vessel to remain within the designated area to avoid impact spread.
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Management and Mitigation Potential Impacts
sequence
Initial Initial Initial Measures
Likelihood Risk Initial
Residual Risk Residual
Con
. Hydrocarbon and spill management plan established according to the Australian Maritime Safety Authority (AMSA) and Port Authority Oil/fuel spills and requirements; Minor Possible Medium Low chemical releases . Staff trained in spill notification and cleanup kits available; and . Australian standards in the handling and storage of hydrocarbons followed. . Loading systems to minimise dust generation where possible; Dust generation during Insignificant Possible Low . Losses during transhipment recorded Low barge loading and reported; and . Monitoring of sediments undertaken. . Stormwater management plan prepared; . Site management and sediment control structures in place according to management plan; Stormwater . During wet season waters in the management and Minor Possible Medium sediment dam will be controlled and Low sediment control at drawn down as far as is practicable; loading area . Dam design will ensure that erosion to receiving habitats is prevented in the event of overtopping; and . Discharge monitoring and reporting in accordance with the plan. . Ensure regulatory requirements are implemented regarding the release Marine pests of ballast water; Moderate Unlikely Medium Low introduction . Offshore location of transhipment limits access to inshore habitats; and . Refer to Chapter 8 – Biosecurity. . All contractors and staff are to be advised of a no fishing policy within Metro Mining tenure areas of the Impacts to local fisheries Minor Unlikely Low Skardon River; and Low . Ensure all marine operations follow the vessel access plan and speed plan for the Skardon River. 6.10 Summary
The study area is located largely on the Weipa Plateau subregion of the Cape York Peninsula Bioregion and occupies part of the Skardon River catchment draining westward into the Gulf of Carpentaria. Mining and cattle grazing are the predominant post-European settlement land uses in the immediate vicinity of the Project; however, the majority of the Project area and surrounds retains extensive remnant vegetation cover.
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The Project area is located in the Skardon River catchment, or drainage sub-basin. While the Skardon River is perennial, many associated watercourses within the Project area are ephemeral and flow only after sustained or intense rainfall. The Skardon River catchment is part of the broader Skardon River–Cotterell River wetland aggregation, which is listed under the Directory of Important Wetlands of Australia (DIWA). The majority of the aggregation occurs north of the Skardon River and Project area, however wetlands associated with the aggregation do occur within the Project area and MLAs, and overlap some of the infrastructure footprint (haul roads and BLF).
The configuration of the Skardon River ranges from a relatively narrow 300 m width at the river entrance, quickly expanding to approximately 1 km upstream. The site of the BLF is located approximately 10 km upstream of the mouth, and is off the main arm of the river with a width of approximately 350 m at this point. The Skardon River and adjacent inshore and offshore areas encompass several marine habitats, including abundant saltmarsh and mangroves, several small patches of seagrass, small rock and oyster reefs within the estuary, offshore coral reef and broad areas of intertidal and subtidal soft substrates that are either bare or variably colonized by macroinvertebrates and macroalgal communities.
A number of marine fauna species considered threatened and/or migratory under State and Commonwealth legislation are known or are considered likely to occur in the vicinity of Project activities including:
. Five marine turtle species with Flatback Turtle known to nest along the beaches west of the Project area. Olive Ridley and Hawksbill Turtle are also known to nest in low densities on western cape York Peninsula;
. Estuarine Crocodile is known to occur in the Skardon River;
. Five dolphin species including Australian Snubfin and Indo-Pacific Humpback Dolphins considered known to occur in the Skardon River estuary;
. Dugong has been observed once before in the Skardon River estuary although the available seagrass habitat does not appear sufficient to support a population; and
. Four sawfish species and Speartooth Shark may utilise habitat in the Skardon River and surrounds.
An analysis of the potential impacts to marine habitats and fauna from the Project and the adjacent SRBP was carried out.
Approximately 20.5 ha of mangroves and 0.25 ha of saltmarsh will be impacted by vegetation clearing for the Project. Clearing for the SRBP will remove a further 0.2 ha of mangrove habitat. Abundant tracts of these vegetation types will remain undisturbed in the surrounding area. No seagrass habitat is currently known within either project’s footprint, however further seagrass surveys will be required prior to construction for the Project’s port facility. Offshore anchorage areas for OGVs have been located away from coral reef habitats identified during surveys for the Project. The construction and operational activities associated with the Project are unlikely to significantly impact marine habitat, given that no dredging or bed-levelling is required within the river.
Increased vessel traffic in the Skardon River and offshore as a result of both projects may have potential impacts including noise impacts on marine fauna, vessel collisions with marine fauna and increased estuarine turbidity and impacts to benthic habitats (such as seagrass) caused by propeller wash. Other minor potential impacts identified include transient noise impacts on marine fauna and ASS exposure during port construction, water quality impacts caused by chemical/fuel spills or
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stormwater borne terrestrial sediment, and the introduction of marine pests. Turtle nesting has potential to be impacted by light spill from the Project, although the nearest known nesting area is located more than 5 km from the edge of the Project and 8 km from the proposed port area.
The risk of the Project activities resulting in the introduction of marine pest species is anticipated to be low given regulatory requirements regarding the release of ballast water and the offshore location of transhipment thereby limiting access to inshore habitats.
Appropriate mitigation measures proposed as part of the Project will minimise additional indirect impacts to marine fauna and habitat within and surrounding the Project area during construction and operational activities. Metro Mining will implement an EMP that will mitigate, manage and monitor the potential impacts described in this assessment. This document will be regularly updated to reflect the current status of the Project mitigation actions, and allow for adaptive improvement of actions where considered necessary. A draft EMP is provided in Appendix K.
It is anticipated that with the appropriate mitigation and management measures the risk of potential impacts occurring to the marine environment and marine fauna will be low with the exception of marine habitat disturbance and marine pest introduction. To fully address the Projects offset requirements a Biodiversity Offsets Strategy Report that details the Project’s estimated extent of significant, residual impacts to MNES and MSES has been prepared and is included as Appendix C. Although no marine fauna species are considered to be significantly impacted by the Project, Metro Mining will investigate opportunities to contribute to local Indigenous organisations contributing to feral pest management and marine turtle nest monitoring on nearby beaches, thereby enhancing local values for threatened marine turtles. 6.11 Commitments
Metro Mining’s commitments for marine ecology management are provided in Table 6-22.
Table 6-22 Commitments – marine ecology Commitments Develop and implement a Project EMP that addresses the construction, operational and decommissioning phases of the Project, including long term marine ecology and estuarine water quality monitoring. Develop and implement a Project-specific Acid Sulphate Soils Management Plan. Establish Significant Species Management Plan to include worker education on local marine fauna, observation reporting procedures and exclusion zones. A Marine Execution Plan will be developed and implemented in consultation with Maritime Safety Queensland and the Regional Harbour Master. A Vessel Traffic Management Plan will be developed and implemented in consultation with Maritime Safety Queensland and the Regional Harbour Master. A Ship-sourced Pollution Prevention Management Plan will be developed and implemented in consultation with Maritime Safety Queensland and the Regional Harbour Master. An Oil Spill Response Plan will be developed and implemented in consultation with Maritime Safety Queensland and the Regional Harbour Master. Establish an Erosion and Sediment Control Plan. This will include controls such as silt curtains during construction of marine infrastructure where required. The concept ESCP is included as Appendix A3. Develop and implement a Marine Pest Monitoring Program in collaboration with Gulf Alumina and Ports North (refer Chapter 8). Submit a Project Biodiversity Offsets Plan to EHP a minimum of three months prior to Project commencement (refer Chapter 5). The Biodiversity Offsets Strategy is included as Appendix C. Implement a seagrass monitoring program for the Skardon River, including the pre-construction footprint that will survey seagrass abundance, distribution and species composition biannually for the duration of the Project. Maintenance of retained mangrove ecosystems surrounding Project activities. Adopt Project light management strategies to minimise potential light spill on turtle nesting habitat.
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Commitments Establish defined vessel access channels that avoid benthic communities and seagrass habitats, go slow zones and speed limits for Project vessels traversing the Skardon River estuary with a preference for vessel movements in the upper tidal range. The channel offshore of the mouth of the Skardon River should be hydrographically surveyed every year (at the end of the wet season). Piling noise during construction of the BLF will be attenuated by: . A 500 m safety exclusion zone will be established around piling works; . Observations by a suitably trained marine megafauna observer will be conducted during piling works; . All impact and vibratory piling works will adopt a soft start approach; . Marine-based pile driving activities will take place during daylight hours; and . Shut-down procedures in the event of marine fauna occurring during piling. Observations of marine fauna will be recorded (including species and location) and incidences of direct interaction such as vessel strike, or near vessel strike reported to the site environmental officer. All vessels involved with the Project will observe the National Biofouling Management Guidelines (refer Chapter 8). The preferred supplier of marine support services will be required to demonstrate compliance with the relevant requirements of both of the above guidelines (refer Chapter 8). Discharge of ballast water by Ocean Going Vessels will be completed outside of Australia’s territorial seas (12 nm of the Australian coastal baseline) in accordance with the Quarantine Act 1908 (refer Chapter 8). 6.12 ToR Cross-reference
Table 6-23 ToR cross-reference – flora and fauna Terms of Reference Section of the EIS 8.2 Land, Flora and Fauna (critical matter) Objectives and performance outcomes The environmental objectives to be met under the EP Act are that the: . activity is operated in a way that protects the environmental values of land including soils, subsoils, landforms and associated flora and fauna . choice of the site, at which the activity is to be carried out, minimises serious environmental harm on areas of high conservation value and special significance and sensitive land uses at adjacent places . location for the activity on a site protects all environmental values relevant to adjacent sensitive use Objectives and outcomes have been listed in Section . design of the facility permits the operation of the site, at which the activity is to 5.4 as per the ToR. be carried out, in accordance with best practice environmental management . avoids significant residual impacts to matters of national and state environmental significance; mitigates impacts where they cannot be avoided and offsets any residual impacts. The performance outcomes corresponding to these objectives are in Schedule 5, Tables 1 and 2 of the EP Regulation. The proponent should supply sufficient evidence (including through studies and proposed management measures) that show these outcomes can be achieved. Information requirements – Flora and Fauna 8.2.12 Describe the likely impacts on the biodiversity and natural environmental Section 6.6. and Section 6.7. - values of affected areas arising from the construction, operation and and see specific sections decommissioning of the project (where known), in accordance with the EHP's EIS listed below for each dot information guidelines relevant to terrestrial and aquatic ecology5. point. Take into account any proposed avoidance and/or mitigation measures. Section 6.8. all. The assessment should include, but not be limited to, the following key elements: Section 6.8.5 and Chapter 7 – . matters of state environmental significance and national environmental Matters of National significance Environmental Significance
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. terrestrial and aquatic ecosystems (including groundwater-dependent Chapter 5 - Terrestrial and ecosystems) and their interaction Aquatic Ecology Section 6.5.1 . biological diversity including listed flora and fauna species and regional Section 6.5.2 ecosystems Section 6.5.4 . the integrity of ecological processes, including habitats of threatened, near- Section 6.5 threatened or special least concern species, movement corridors and fish passage . the integrity of landscapes and places, including wilderness and similar natural Section 6.5 places Chapter 4 – Land Chapter 18 – Hazard and . chronic, low-level exposure to contaminants or the bio-accumulation of Safety contaminants Chapter 19 – Coastal Environment Impacts on marine, terrestrial and aquatic ecosystems and associated native flora and fauna due to wastes and pollutants at the site, particularly those related to any form of toxicants in: . surface water and groundwater Section 6.6.1.2 . natural water courses Section 6.6.1.4 Section 6.6.1.5 . stormwater run-off . surface run-off . run-off from any bunded areas holding chemicals and/or sewage treatment plant . run-off from surface spoil o likely impacts (noise, strikes, habitat disturbance) on estuarine and marine Section 6.6.2.1 fauna due to shipping/barge movements and/or piling programs for Section 6.6.2.2 jetties/wharfs etc. o likely impacts of light spill on adjacent terrestrial and marine ecosystems Section 6.6.2.3 and fauna o a description of alternative options for the location and construction on Section 2.5 of Chapter 2 – haul roads and barge landing that reduce impacts to marines plants and Description of the Project. fisheries resources. Section 6.6.1.1 8.2.13 Describe any actions of the project that require an authority under the Section 6.6.1.6 Nature Conservation Act 1992, and/or would be assessable development for the Chapter 1(Section 1.6 – purposes of the Vegetation Management Act 19996, the Regional Planning Interests Project Approvals) Act 2014, the Fisheries Act 1994 and/or the Sustainable Planning Act 2009. 8.2.14 Propose practical measures for protecting or enhancing natural values, and Throughout Section 6.8 assess how the nominated quantitative indicators and standards may be achieved Section 6.8.2.5 for nature conservation management. In particular, address measures to protect or preserve any threatened or near- Section 6.8.2 threatened species. 8.2.15 Specifically address any obligations imposed by State or Commonwealth Chapter 5 – Terrestrial and legislation or policy or international treaty obligations, such as the China–Australia Aquatic Ecology Migratory Bird Agreement, Japan–Australia Migratory Bird Agreement, or Republic of Korea–Australia Migratory Bird Agreement. 8.2.16 Assess the need for buffer zones and the retention, rehabilitation or planting Section 6.6.1.6 of movement corridors, and propose measures that would avoid the need for Chapter 5 – Terrestrial and waterway barriers, or propose measures to mitigate the impacts of their Aquatic Ecology construction and operation. The measures proposed for the progressive rehabilitation of disturbed areas should Section 4.8.3 of Chapter 4 – include rehabilitation success criteria in relation to natural values that would be Land used to measure the progress.
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Section 6.8 – Project 8.2.17 Describe how the achievement of the objectives would be monitored and management plans described audited, and how corrective actions would be managed. Appendix K – Project EMP Section 5.9.1.2 and 5.9.1.3 of Chapter 5 – Terrestrial and Proposals for the rehabilitation of disturbed areas should incorporate, where Freshwater Ecology appropriate, provision of nest hollows and ground litter. Section 4.8.3 of Chapter 4 – Land. Offsets 8.2.18 Where Queensland legislation or a specific-issue offset policy requires an Section 5.10 of Chapter 5 – offset for a significant residual impact on a particular natural environmental value, Terrestrial and Aquatic the offset proposal(s) shall be presented in a form consistent with relevant Ecology and Appendix C – legislation and policy. Offsets. Section 5.10, Chapter 5 – 8.2.19 The proposed offsets should be consistent with the requirements set out in Terrestrial and Aquatic any applicable legislation or specific-issue offset policies. Ecology
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