Flora Survey and Vegetation Mapping for TSF3 Footprint - Site B&D and Northern Areas
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Golden Grove –Flora survey & vegetation mapping for TSF3 footprint- Site B&D and February 2009 northern areas. Prepared by: Yilgarn Traders 333 David Road, Waggrakine, WA 6530 Golden Grove - Flora survey and Vegetation mapping for TSF3 footprint - Site B&D and northern areas. Prepared for OZ Minerals Ltd, PMB 7, Geraldton 6530 February 2009 1 Yilgarn Traders Golden Grove –Flora survey & vegetation mapping for TSF3 footprint- Site B&D and February 2009 northern areas. Reliance on Data & Environmental Conditions The author has made every effort to interpret data correctly based on prior knowledge of flora and vegetation associations, earlier vegetation reports of the area and individual plant specimen identification. While this report has relied on data gathered throughout April to September and has captured the majority of flora, it may not represent 100% of flora present. Scope or Services The scope of work has been limited to data collection, interpretation, analysis and a report, it has been agreed that OZ Minerals Ltd transfer GIS mapping co-ordinates into their internal system to produce the final maps to accompany the report. The report and mapped associations are prepared and supplied to OZ Minerals in a digital format. Other Limitations The author will not be liable to update or revise the report due to any changing events, facts occurring or becoming apparent after the report date. Dryland Permaculture Nursery & Research Farm T/as Yilgarn Traders 333 David Road Waggrakine, Western Australia Ph: 08 99381628 Email: [email protected] ABBREVIATIONS The following abbreviations have been used throughout this report: var. Variety spp. Multiple species - used when genus is known sp. Species - used when genus is known ssp. Subspecies (Genus) ? (species) Genus is known and unsure of species identification 2 Yilgarn Traders Golden Grove –Flora survey & vegetation mapping for TSF3 footprint- Site B&D and February 2009 northern areas. SUMMARY OZ Minerals Golden Grove Ltd are investigating site options for a new ‘life of mine’ Tailings Storage Facility No.3 (TSF3) as the capacity of the current Tailings Storage Facility No.2 (TSF2) is diminishing. Three locations have been analysed against environmental, economic and anthropological factors. Site B and D are two of these locations and have been examined within this survey. The sites are 136 and 122 hectares respectively. Note: Site A is located to the south west of these sites in an area west of TSF1 and not in the scope of this report. Yilgarn Traders was commissioned by OZ Minerals Ltd to undertake vegetation mapping and a flora survey of 630 hectares of their leases at Golden Grove situated between Paynes Find and Yalgoo. An initial autumn survey (Yilgarn Traders, June 2008) of Site B & D was conducted after heavy rains. A second survey during spring also spanned into areas north of these sites in order to put Site B & D into context with the northern flora (630 hectares). To the west of this site lies a Banded Iron formation (BIF) hill, this area was outside of the survey area. Two priority taxa as defined by the Western Australian Department of Environment and Conservation (2008); Acacia speckii and Calytrix uncinata were located within both Site B and D. These species are currently Priority 3 taxa. A third annual Priority 3 species; Gunniopsis rubra was located in the northern survey area outside of Site B and D. Sites B and D overlapped and contained the same population of Calytrix uncinata consisting of 78 individuals. Calytrix uncinata commonly occurs throughout Golden Grove’s leases with 18 populations recorded, estimated to contain thousands of plants. Impacting this population would have a low effect on this taxon’s local conservational significance. Impacting Acacia speckii would remove 13% of Golden Grove’s four known populations in Site B and 18% in Site D. Ascertaining Acacia speckii’s conservational significance regionally is recommended. Site D abuts a BIF hill and adverse effects to the BIF vegetation such as dust accumulation from the surface of the Tailings Storage Facility 3 should be taken into account and adequate management strategies ensured. Over the entire survey site 19 different vegetation associations were recorded with 219 vascular plants identified; half of these are only apparent during winter and spring. The mapped associations consisted of 80% Acacia shrublands located mainly throughout the plains and drainage lines. Thryptomene heaths with emergent shrubs were found growing on low ridges and hardpans. Chenopod heaths with salt tolerant shrubs occurred throughout the lower plains in depressions. The associations mapped were strongly connected to their topography and soil type. Twelve different vegetation associations were mapped within Site B and D. 3 Yilgarn Traders Golden Grove –Flora survey & vegetation mapping for TSF3 footprint- Site B&D and February 2009 northern areas. CONTENTS SUMMARY ............................................................................................................................................ 3 1. INTRODUCTION ............................................................................................................................... 6 1.1. Background ............................................................................................................................. 6 1.2. Scope of Works ....................................................................................................................... 6 2. METHODS .......................................................................................................................................... 7 2.1. FLORA ................................................................................................................................... 7 2.1.1. Rare and Priority Flora .................................................................................................... 7 2.2. VEGETATION ASSOCIATIONS ......................................................................................... 7 3. RESULTS ............................................................................................................................................ 8 3.1. FLORA ................................................................................................................................... 8 3.1.1. Rare and Priority Flora .................................................................................................... 8 3.2. VEGETATION ASSOCIATIONS ....................................................................................... 11 3.2.1. D1 – Drainage line 1 ..................................................................................................... 12 3.2.2. D4 – Drainage line 4 .................................................................................................... 13 3.2.3. D5 – Drainage line 5 ..................................................................................................... 14 3.2.4. D6 – Drainage creekline 6 ............................................................................................ 15 3.2.5. HS – Hillslope ............................................................................................................... 16 3.2.6. P8 – Plains 8 .................................................................................................................. 17 3.2.7. P9 – Plains 9 .................................................................................................................. 18 3.2.8. P10 – Plains 10 .............................................................................................................. 19 3.2.9. P11 – Plains 11 .............................................................................................................. 20 3.2.10. P13 – Plains 13 .............................................................................................................. 21 3.2.11. P14 - Plains 14 .............................................................................................................. 22 3.2.12. P15 - Plains 15 .............................................................................................................. 23 3.2.13. R2 – Ridge 2 ................................................................................................................. 24 3.2.14. R3 – Ridge 3 ................................................................................................................. 25 3.2.15. S3 – Salt flat 3 ............................................................................................................... 26 3.2.16. S5 – Salt flat 5 ............................................................................................................... 27 3.2.17. S6 – Salt flat 6 ............................................................................................................... 28 3.2.18. UP1 – Upper plains 1 .................................................................................................... 29 3.2.19. UP4 – Upper plains 4 .................................................................................................... 30 4. DISCUSSION .................................................................................................................................... 31 5. RECOMMENDATIONS ................................................................................................................... 33 4 Yilgarn Traders Golden Grove –Flora survey & vegetation mapping for TSF3