Main Roads Western Australia Galvans Gorge to Barnett Gorge (SLK 286.5 - 324.1) Preliminary Environmental Impact Assessment April 2009 Contents Summary of Statutory Approvals Required i 1. Introduction 2 1.1 Background 2 1.2 Purpose of this Report 2 2. Project Description 3 3. Environmental Aspects 5 4. Existing Environment 7 4.1 Climate 7 4.2 Landuse 8 4.3 Topography and Soils 8 4.4 Hydrology 8 4.5 Reserves and Conservation Areas 9 4.6 Vegetation 10 4.7 Flora 12 4.8 Fauna 14 4.9 European Heritage 16 4.10 Aboriginal Heritage 16 4.11 Noise and Vibration 17 4.12 Dust 17 4.13 Visual Amenity 17 4.14 Public safety and Risk 18 5. Vegetation Clearing 19 5.1 DEC’s “Ten Clearing Principles” 19 5.2 Clearing in Environmentally Sensitive Areas 19 6. Potential Impacts 20 7. Recommendations and Approvals Required 23 8. Stakeholder Consultation 24 9. References 25 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) Preliminary Environmental Impact Assessment Table Index Table 1 Key features of the Main Roads Project 4 Table 2 Environmental Aspects Considered for the Project 5 Table 3 Vegetation Extent and Status 10 Table 4 Regional Assessment of Vegetation Extent (Shepherd, 2005) 11 Table 5 Weeds Of National Significance (WONS), Declared Plants and Regionally significant weed species that may occur in the Study Area 13 Table 6 Aboriginal heritage Sites that may be impacted by the Proposed Project 17 Table 7 Assessment of Environmental and Social Aspects and Impacts 20 Table 8 Recommendations and Approvals required for the Project 23 Table 9 Conservation Categories and Definitions for EPBC Act Listed Flora and Fauna Species. Table 10 Conservation Codes and Descriptions for DEC Declared Rare and Priority Flora Species. Table 11 Significant Flora Species identified in the Threatened Flora Database Search Results Table 12 Western Australia Wildlife Conservation Act (1950) Conservation Codes Table 13 DEC Priority Fauna Codes Table 14 Threatened fauna occurring, or likely to occur, in the Study Area as indicated by the EPBC Act Protected Matters Search Tool and the DEC’s Threatened Fauna Database search Figure Index Figure 1 Location Map Figure 2 Study Area and Environmental Constraints 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) Preliminary Environmental Impact Assessment Appendices A Flora B Fauna C Search Results D Aboriginal Heritage E DEC’s “Ten Clearing Principles” 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) Preliminary Environmental Impact Assessment Summary of Statutory Approvals Required No statutory approvals will be required for the Project. However, further permits may be required, as follows: » If groundwater is required, Main Roads will need to apply for a 26D Licence under theRights in Water and Irrigation Act 1914 to construct bores in this area and/or apply for a 5C Licence for abstraction of water. » Main Roads will need to apply for a Section 17 Permit to Interfere with Bed and Banks under the Rights in Water Irrigation Act 1914 if road upgrades impact on the Bed and Banks of the Barnett River; and » Land acquisition for material extraction on Mt Barnett and Gibb Pastoral Leases. Refer to Section 7 for recommendations where further investigation is likely to be required for the Project. 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) i Preliminary Environmental Impact Assessment 1. Introduction 1.1 Background Main Roads Western Australia (MRWA) is currently planning to commence road formation and drainage improvements along approximately 37 km of the Gibb River Road (SLK 286.5 – 324.1) (the Project). Figure 1 identifies the location of the proposed Project. The proposed road formation and drainage improvements require the sourcing of gravel and other fill materials. Eight material areas have been proposed as suitable areas from which to extract road•building materials for the proposed Project. These areas will be investigated to locate naturally occurring gravel material suitable for the Project works. The Gibb River Road is a predominantly gravel road that was originally built to provide road access to remote Kimberley stations. It runs approximately 650 km between Derby and intersects with the Great Northern Highway between Wyndham and Kununurra. The proposed work will: » improve the road condition, » provide increased serviceability, » reduce maintenance and freight costs; and » improve the level of serviceability to the local community. 1.2 Purpose of this Report MRWA requires a Preliminary Environmental Impact Assessment (PEIA) for the proposed Project. This report details the findings of the PEIA undertaken for the Study Area, and » describes the significant aspects of the existing environment; » details the primary environmental and social impacts of the proposed works; » identifies any matters likely to warrant referral to the Environmental Protection Authority and/or the Commonwealth Department of the Environment, Water, Heritage and the Arts; and » provides recommendations for additional investigations that may be required to clarify the expected environmental impacts of the proposed works. 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) 2 Preliminary Environmental Impact Assessment 2. Project Description Table 1 outlines the key features of the Project, which includes the following Study Area that this PEIA has been undertaken for: » A 100 m wide corridor on both the left hand side (LHS) and right hand side (RHS) of the Gibb River Road from SLK 286.5 • 324.1; and » Eight Material Investigation Areas. The location and Study Area extent for the road formation and drainage improvements, as well as each of the eight Material Investigation Areas are shown in Figure 2. 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) 3 Preliminary Environmental Impact Assessment Table 1 Key features of the Main Roads Project SLK /Area Proposed Works Study Area Proposed Clearing (ha) Gibb River Road – SLK 286.5 to Road formation and A 100 m wide corridor on both the LHS and Clearing will occur for: 324.1 Drainage Improvements RHS of Gibb River Road from SLK 286.5 • 324.1. » Minor road widening; » A temporary side track; and » Establishment of offshoot drains. Material Investigation Area 1 Source Material Area Area 1 comprises approximately 24 ha. Native vegetation will be cleared in areas where source material is identified. Located on the RHS of Gibb River Road. Material Investigation Area 2 Source Material Area Area 2 comprises approximately 356.1 ha. Native vegetation will be cleared in areas where source material is identified. Located on the RHS of Gibb River Road. Material Investigation Area 3 Source Material Area Area 3 comprises approximately 27 ha. Native vegetation will be cleared in areas where source material is identified. Located on the LHS of Gibb River Road. Material Investigation Area 4 Source Material Area Area 4 comprises approximately 93.1 ha. Native vegetation will be cleared in areas where source material is identified. Located on the RHS of Gibb River Road. Material Investigation Area 5 Source Material Area Area 5 comprises approximately 74.1 ha. Native vegetation will be cleared in areas where source material is identified. Located on the LHS of Gibb River Road. Material Investigation Area 6 Source Material Area Area 6 comprises approximately 101.5 ha. Native vegetation will be cleared in areas where source material is identified. Located on the LHS of Gibb River Road. Material Investigation Area 7 Source Material Area Area 7 comprises approximately 128.2 ha. Native vegetation will be cleared in areas where source material is identified. Located on the LHS of Gibb River Road. Material Investigation Area 8 Source Material Area Area 8 comprises approximately 33.6 ha. Native vegetation will be cleared in areas where source material is identified. Located on the RHS of Gibb River Road. 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) 4 Preliminary Environmental Impact Assessment 3. Environmental Aspects The key environmental aspects considered for the proposed Project are listed in Table 2. The potential impacts for the relevant environmental aspects are examined in more detail in Sections 4 and 5. ***Note: Where issues were not considered relevant to the Project a justification for their exclusion has been included in Table 2***. Table 2 Environmental Aspects Considered for the Project Environmental Aspect Yes No Comments Adjacent Land•uses Ö Addressed in Section 4.2 Surface waters / drainage Ö Addressed in Section 4.4.1 and 4.4.2 (watercourses, stormwater disposal, water quality, proclaimed waterways) Groundwater Ö Addressed in Section 4.4.3 Wetlands Ö The Study Area does not comprise any known wetland areas. Salinity Ö No salinity issues are known to occur within the Study Area. Reserves and conservation areas; Ö Addressed in Section 4.5 including Environmentally Sensitive Areas Vegetation – clearing Ö Addressed in Section 5 Vegetation – associations, Ö Addressed in Section 4.6.2 representativeness and clearing Vegetation – threatened species Ö Addressed in Section 4.6.3 and 4.7.1 and communities Vegetation – dieback and other Ö No dieback exists within the Kimberley diseases or pathogens Region. No other diseases or pathogens are considered relevant to the Study Area. Vegetation – weeds Ö Addressed in Section 4.7.3 Fauna Ö Addressed in Section 4.8 Heritage (non•indigenous) Ö Addressed in Section 4.9 Aboriginal heritage Ö Addressed in Section 4.10 Noise and Vibration Ö Addressed in Section 4.11 Air Quality Ö The Project is not expected to impact upon regional air quality. 61/23753/13879 Galvans Gorge to Barnett Gorge (SLK 286.5 • 324.1) 5 Preliminary Environmental Impact Assessment Environmental Aspect Yes No Comments Dust Ö Addressed in Section 4.12 Visual Amenity Ö Addressed in Section 4.13 Public safety and risk Ö Addressed in Section 4.14 Contaminated sites Ö No known contaminated sites are located within the Study Area.