Marine Mammals in Finnish, Russian and Estonian Waters in Relation to the Nord Stream 2 Project
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Commissioned Report from DCE – Danish Centre for Environment and Energy Marine mammals in Finnish, Russian and Estonian waters in relation to the Nord Stream 2 project Expert Assessment Signe Sveegaard Anders Galatius Jakob Tougaard Aarhus University, Department of Bioscience Revision: 2017.03.02 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA Data sheet Series title: Commissioned Report from DCE – Danish Centre for Environment and Energy Title: Marine mammals in Finnish, Russian and Estonian waters in relation to the Nord Stream 2 project Subtitle: Exp ert Assessm ent Authors: Signe Sveegaard, Anders Galatius, Jakob Tougaard Institution: Aarhus University, Department of Bioscience Publisher: Aarhus University, DCE – Danish Centre for Environment and Energy © URL: http :/ / d ce.a u.dk/ en Year of publication: March 2017 Editing completed: 2017.03.02 Referee: Line A. Kyhn Financial support: Rambøll/Nord Stream 2 Cover photo: Grey seal, Svend Tougaard Please cite as: Sveegaard, S., Galatius, A. & Tougaard, J. 2017. Marine mammals in Finnish, Russian and Estonian waters in relation to the Nord Stream 2 project – Exp ert Assessm ent. Aarhus University, DCE – Danish Centre for Environment and Energy, Commissioned report from DCE – Danish Centre for Environment and Energy, to Rambøll/ Nord Stream 2. Number of pages: 82 W-PE-EIA-PFI-REP-805-DCE020EN-05 Contents Pref a ce 6 1. Introduction 7 1.1 Purpose and structure of this report 7 2. Introduction to impacts 8 3. Potential sources of impacts during construction 9 3.1 Underwater noise 9 3.2 Sediment spill 11 3.3 Unplanned events - Oil spill 12 3.4 Icebreaking caused by service vessels 12 4. Potential sources of impacts during pre-commissioning and commissioning 13 4.1 Pre -commissioning 13 4.2 Commissioning 13 5. Potential sources of impacts during operation 14 5.1 Underwater noise 14 5.2 Changes in the habitat 15 5.3 Unplanned events 16 6. Assessment methodology 17 Sensitivity of marine mammals 17 Impact magnitude 20 Asse ssm e nt le ve ls 21 7. Sensitivities of marine mammals 23 7.1 Underwater noise 23 7.2 Sediment spill 36 Unplanned events – Oil spill 37 Changes in the habitat 38 Unplanned events – Gas release 38 7.3 Seasonal sensitivity 39 8. Magnitude of impact 40 8.1 Underwater noise 40 8.2 Sediment spill 51 8.3 Changes in the habitat 52 8.4 Health effects caused by contaminants 52 8.5 Oil spill 53 8.6 Ga s relea se 53 9. Assessment of impact in the construction period without mitigation measures 54 9.1 Underwater No ise 54 9.2 Sediment spill 62 9.3 Unplanned events 63 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA 10. Assessment of impact in the operation period 63 10.1 Underwater noise from pipeline 64 10.2 Changes in the habitat 64 10.3 Unplanned events 65 11. General approach to mitigation 66 Reduction of generated noise 66 Reduction of radiated noise 66 Reduce received noise 66 12. Assessment of impact with mitigation 67 12.1 Mitigation measures used for the Nord Stream pipeline, Finnish waters 67 12.2 Effects of sea l sc a re r 68 12.3 Co nseq ue nce s fo r a sse ssm ent – blast injury 69 12.4 Consequence for assesment - PTS 70 12.5 Conclusion on mitigation 70 13. Summary tables of assessment with and without mitigation 70 13.1 Harbour porpoise 71 13.2 Grey Seal 72 13.3 Ringed seal 73 14. Assessment of impact in Natura 2000 areas in EU waters 74 14.1 Natura 2000 sites 74 15. Conclusion 76 16. References 78 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA 5 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA Preface This report was commissioned by Nord Stream 2 (through Rambøll) and constitutes expert assessments regarding marine mammals and intended as input to the Environmental Impact Assessment of the proposed Nord Stream 2 pipeline through Russian and Finnish waters. The assessments build upon exsisting knowledge, summarized in the accompanying baseline report, and draws on distribution data for marine mammals obtained from HELCOM and directly from researchers, including DCE/Aarhus University, as well as exsisting knowledge regarding effects on marine mammals.Assessments of impact from underwater noise and sediment spill are based on predictive modelling of spatial extent of noise and sediment plumes conducted by Rambøll and documented in separate reports. Conclusions in this report are not intended to stand alone, but should be read in proper context of the full environmental impact assessment of the project. 6 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA 1. Introduction 1.1 Purpose and structure of this report The purpose of this report is to assess the potential impacts on marine mammals in relation to the construction and operation of the Finnish and Russian sections of the proposed gas pipeline Nord Stream 2 (Nord Stream 2 Pipeline system – NSP2). The maximum impacts during construction without mitigation measuresand with mitigation measures are assessed. The construction and operation may have impacts on marine mammals in Finnish, Estonian and Russian waters and in these waters, the most relevant marine mammal species are grey seal (Halichoerus grypus grypus) and ringed seal (Pusa hispida botnica) but also harbour porpoises are occasionally present (Phocoena phocoena). This report is based on the following: • The information and studies conducted during the Environmental Impact Assessments for marine mammals from Nord Stream (NSP). • The information described in the NSP2 baseline report for marine mammals (Teilmann, Galatius, and Sveegaard 2017). • The models on sedimentation and underwater noise in Russian and Finnish waters performed by Rambøll. • Relevant literature. No new fieldwork was conducted. The report describes the pressures related to the periods of construction, pre-commissioning, commisioning and operation of the gas-pipeline (chapter 2, 3, 4 and 5). This is followed by a chapter on interpretation of the EIA methodology in relation to marine mammals (chapter 6) . Chapter 7 assesses the sensitivity of marine mammals with regard to the potential impacts including criteria for noise levels. In chapter 8 the magnitude of impacts are assessed. Chapter 9 combines the information on sensitivity and impact magnitude in order to conclude on the overall significance of each impact during construction. Chapter 9 can be considered as a worst case assessment, since no mitigation measures is taken into consideration. Chapter 10 assesses impacts during operation by the combination of impacts magnitude and species sensitivity to the impacts. In Chapter 11, different methods potentially available on the market to mitigate the impacts of munition clearances are described on a general level. Chapter 12 focuses on the mitigation measures to which NSP2 has committed and how these can reduce the potential impacts during construction. A summary of the assessments described in chapter 9, 10 and 12 is presented in Chapter 13 and Chapter 14 provides an assessment of impact on Natura 2000 areas. Chapter 15 provides the conclusions of the assessment. Assessment of impact during decommissioning are not included here, since this depends upon practice/methodology available at the time decommissioning becomes relevant (approx. 50 years from construction). 7 W-PE-EIA-PFI-REP-805-DCE020EN-05 Marine mammals in the Baltic Sea in relation to the Nord Stream 2 project – EIA 2. Introduction to impacts The central question in the context of the NSP2 project and marine mammals answered in this report is whether the construction and operation of the pipeline will have an impact (positive or negative) on the individual animals as well as on the population (i.e. on abundance and distribution). Whether such an impact is acceptable or not is a political consideration, and is not addressed here. Assessing the impact at the population level is often difficult unless all factors related to the population structure and abundance of the animals, as well as all other factors affecting their survival in relation to direct and indirect impacts are known. In this report, information on the animals using the impacted areas and the status of their populations are not well known and further data e.g., from further tagging of seals, habitat suitability modelling and abundance surveys would be of high relevance. The assessment of the impacts from the construction and operation of the pipeline is based on assumptions about links from immediate impact to population level consequences and hence associated with uncertainty. The main pressures on marine mammals during construction of the gas pipeline are assumed to be underwater noise from munition clearances and construction activities, and sediment spill from seabed intervention activities. Underwater noise is a potentially significant disturbing factor. The pipeline construction will consist of various noisy activities, such as pipelaying with operation of cranes and winches, anchor handling, and rock placement. The ship engines and propellers will also be a source of noise. Munitions have to be cleared from the seabed prior to construction to ensure a safe installation of the pipelines and this munition clearance has by far the largest impact on marine mammals including potential casualties and permanent hearing damage. Sediment spill will occur primarily during munitions clearance, rock placement and dredging at the Russian landfall, but also from the pipe laying and anchor handling. The consequences of sediment spill on marine mammals relate to the increased turbidity of the water, possible release of toxic contaminants to the water column and a possible decrease in prey availability through secondary effects of the resuspended sediment on fish.