Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment Report Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment REPORT for Energy Australia by Molino Stewart Pty Ltd ACN 067 774 332 JUNE 2007 38 Cowper St Parramatta NSW 2150 Tel (02) 9891 5399 Fax (02) 9893 9806 Email: [email protected] Web: www.molinostewart.com.au CONTENTS 1 INTRODUCTION 1 1.1 Background 1 1.2 Approach 2 2 METHODS 3 2.1 Desktop Analysis 3 2.2 Field Inspection 3 2.2.1 Kurnell STS 4 2.2.2 Bunnerong STS 4 2.2.3 Cable Route 5 3 RESULTS 7 3.1 Desktop Analysis Results 7 3.1.1 Bunnerong 7 3.1.2 Kurnell STS 7 3.1.3 Road Reserve Cable Route 7 3.1.4 Database Search Results 7 3.1.5 Threatened Species Legislation 8 3.1.6 Subject Threatened Species 10 3.1.7 Other Ecological Issues 11 3.2 Field Inspection Results 12 3.2.1 Bunnerong STS 12 3.2.2 Kurnell STS 14 3.2.3 Cable Route 16 4 DISCUSSION 17 4.1 Bunnerong STS 17 4.2 Kurnell STS 18 4.3 Northern Cable Route 19 4.4 Southern Cable Route 20 4.5 Recommendations 20 4.6 Conclusions 21 5 REFERENCES 22 Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment Report i Contents APPENDICES Appendix A Flora Lists Appendix B Subject Threatened Fauna Species Appendix C Cable Route Sections Appendix D EPBC Act Protected Matters Report LIST OF TABLES Table 1: An indicative list of potential threatened species based on Wildlife Data Base Searches 8 LIST OF FIGURES Figure 1 Location of Proposed Works 1 Figure 2: Kurnell STS depicting possible cable route approaches. Orange outlines depict proposed building locations, solid orange are existing buildings. Mauve area to the south is RAMSAR wetland. 4 Figure 3: Bunnerong STS depicting feeder cable routes (red) connecting to Bunnerong south and the optional connection to Bunnerong north (yellow dashed). 5 Figure 4: Cable routes a) Northern La Perouse to Bunnerong STS. b) Southern Silver Beach to Kurnell STS (Yellow dots indicate where assessment was carried out and photographic records taken.) 6 Figure 5: Bunnerong South STS area proposed for vegetation clearance. 16 Figure 6: Proposed gazettal area of Eastern Suburbs Banksia Scrub Endangered Ecological Community on the Bunnerong STS site. 18 ii Energy Australia 1 INTRODUCTION 1.1 Background During the next decade EnergyAustralia must replace ageing infrastructure in the Sydney CBD and the inner metropolitan area. It has been identified that replacement of two existing high voltage feeders which currently connect EnergyAustralia’s Bunnerong subtransmission substation (“STS”) at Matraville with its Canterbury STS at Earlwood, must be achieved by late 2008. The preferred replacement for the feeders, known as Feeders 908 and 909, however, is a new connection between Bunnerong and Kurnell across Botany Bay. It is proposed that the new feeders would take the following route: ¾ from Bunnerong STS, following the road alignments to La Perouse (3.2km); ¾ under the National Park at La Perouse by way of horizontal directional drilling (0.5km); ¾ across Botany Bay by way of submarine cable to a section of Silver Beach situated outside (but next to) the National Park at Kurnell (2.2km); and ¾ from Silver Beach to Kurnell STS, following the road alignments (1.5km). At Bunnerong STS, little work is proposed other than the laying of the cables within the site and connecting them to new terminations and existing equipment/apparatus. The new connections would provide an opportunity to upgrade Kurnell STS so that supplies to the Kurnell Peninsula are more secure, as well as facilitating the additional power into the CBD and inner metropolitan area. The proposed works at the Kurnell STS comprise: ¾ Replacement of the ageing outdoor high voltage switch gear with a building to house the Gas Insulated Switchgear and Control and Protection equipment to which the new cables would be connected. Three new transformers in new transformer bays. ¾ An underground retention system which would capture any oil spilled in the unlikely event of rupture of a transformer. The Project will be known as the ‘Botany Bay Cable Project’ and the location of the proposed works is shown in the following figure. Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment Report 1 Terrestrial Ecology Assessment Report3.doc/7/06/2007 8:12:00 AM Figure 1 Location of Proposed Works This development will involve modifications to facilities at both sub-transmission stations, the installation of terrestrial underground feeder cables and a submarine section under the sea bed of Botany Bay linking the two sides of the Bay. The overall proposal will necessitate some vegetation clearance within or adjacent to the grounds of the two STS to accommodate enlarged compounds, new switching gear and associated buildings. The installation of underground cables will mainly follow existing formed road reserves with the exception of its crossing of the ‘La Perouse’ historic heritage section of Botany Bay National Park, its crossing of the sea bed of Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment Report 1 Terrestrial Ecology Assessment Report3.doc/7/06/2007 8:12:00 AM Botany Bay itself and its crossing of the Silver Beach front at Kurnell adjacent to the ‘Cooks Landing Place’ historic heritage section of Botany Bay National Park. 1.2 Approach This report documents an assessment of the likely ecological impacts resulting from the terrestrial components of the Energy Australia proposal as briefly outlined above. The aims and objectives of this study are to: ¾ Review existing information on the terrestrial ecology of the two sub- transmission stations and the land based section of the cable route itself; ¾ Determine the known or likely presence of any threatened species or their habitat (including endangered populations and ecological communities) as listed under both the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and NSW Threatened Species Conservation Act 1995 (TSC Act) through site and cable route inspections and; ¾ Identify any other matters of National environmental significance; and ¾ Identify measures and strategies to avoid, minimise, mitigate/ameliorate and offset any likely impacts on threatened species or other ecological matters of national environmental significance. 2 Energy Australia Terrestrial Ecology Assessment Report3.doc/7/06/2007 8:12:00 AM 2 METHODS 2.1 Desktop Analysis A desktop analysis was undertaken using Geographic Information System Software – ArcView GIS. This involved acquiring, overlaying and analysis of various digital data sets including: ¾ Tenure ¾ Landuse/Zoning ¾ Cadastre ¾ Vegetation coverage ¾ Environmental values – (RAMSAR, SEPP etc) ¾ Orthorectified aerial photographs ¾ Topographic and ¾ Flora and Fauna including threatened species, JAMBA and CAMBA species records. An EPBC Act Protected Matters Report was generated courtesy of the Department of Environment and Heritage (DEH) documenting the various matters of National Environmental significance that may be affected by the proposal. These initial investigations were undertaken to determine indications of constraints or possible issues for further consideration and that would require addressing within a thorough ecological assessment of the possible impacts of the proposal as outlined. This analysis generated indicative maps, species lists and an issues list that required further consideration and discussion. 2.2 Field Inspection Two field investigations were undertaken along the proposed cable route and at the Bunnerong and Kurnell sub transmission substations (STS) and their immediate environs. An initial investigation was carried out on 4th August 2006 and again on 20th September 2006. A floristic survey and a general fauna survey were undertaken to validate previous studies and determine the extent or likelihood for direct or indirect impacts on threatened species and/or their habitat likely to result from the understood scope of works required by the current proposal. Futhermore the assessment process took into account relevant considerations as outlined in the NSW Department of Environment and Climate Change Draft “Threatened Biodiversity Survey and Assessment Guidelines for Developments and Activities” when undertaking the STS sites and cable route inspections. Botany Bay 132kV Cable Project – Terrestrial Ecology Assessment Report 3 Terrestrial Ecology Assessment Report3.doc/7/06/2007 8:12:00 AM 2.2.1 Kurnell STS The site inspections and surveys of the Kurnell STS (Lot 1 DP 869365) involved assessing on foot the perimeter fence of the compound and examining the flora species present both on the reclaimed site comprising the STS boundary, as well as the flora species and vegetation community types surrounding the subject land, the drainage features on the subject land and on neighbouring properties including adjacent road/drainage easements. A general fauna habitat assessment was undertaken to ascertain preliminary findings that might indicate that targeted or more specialised surveys were warranted. The precise entry point for the cable from its approach along Captain Cook Drive was not able to be accurately determined nor was it possible to obtain precise positioning of the proposed buildings at the Kurnell STS prior to the site surveys. Two possible cable entry routes were given consideration and proposed building impacts were reassessed, post site visit, once building location plans became available. The cable route approaches assessed are depicted in Figure 2, below. Figure 2: Kurnell STS depicting possible cable route approaches. Orange outlines depict proposed building locations, solid orange are existing buildings. Mauve area to the south is RAMSAR wetland. 2.2.2 Bunnerong STS Site inspections and surveys of the Bunnerong STS (Lot 102 DP 805244) involved traversing the various internal roads and tracks on 4th August 2006 within the Bunnerong STS perimeter fence but outside the internal fenced compound areas containing the electrical switching gear. A subsequent external perimeter fence survey was undertaken on 20th September 2006. The assessment also involved giving consideration to a number of possible internal cable routes that were discussed on site with Energy Australia personnel.