Appendix 12.3: Underwater Noise Study URS-EIA-REP-204635 South Stream Pipeline – Russian Sector – Underwater Sound Analysis Submitted to: South Stream Transport B.V. Authors: Mikhail Zykov Loren Bailey Terry Deveau Roberto Racca JASCO Applied Sciences Ltd. 22 November 2013 Suite 202, 32 Troop Ave. Dartmouth, NS B3B 1Z1 Canada P001226-002 Phone: +1-902-405-3336 Document 00691 Fax: +1-902-405-3337 Version 1.0 www.jasco.com JASCO APPLIED SCIENCES South Stream Pipeline – Russian Sector – Underwater Sound Analysis Suggested citation: Zykov, Mikhail, et al. 2013. South Stream Pipeline – Russian Sector – Underwater Sound Analysis. JASCO Document 00691, Version 1.0. Technical report by JASCO Applied Sciences for South Stream Transport B.V. i South Stream Pipeline – Russian Sector – Underwater Sound Analysis JASCO APPLIED SCIENCES Contents 1. INTRODUCTION .......................................................................................................................1 1.1. Scope of the Study ........................................................................................................................ 1 1.2. Project Overview .......................................................................................................................... 1 1.2.1. Near-shore Section .............................................................................................................. 2 1.2.2. Offshore Section, Mid-depth Water. .................................................................................... 2 1.2.3. Offshore section, Deep Water.............................................................................................. 2 1.3. Background–Underwater Acoustics .............................................................................................. 3 1.3.1. Types of Sound Sources ...................................................................................................... 3 1.3.2. Sound Level Metrics ........................................................................................................... 3 1.1.1. Transmission Loss .............................................................................................................. 4 1.1.2. Source Levels ..................................................................................................................... 4 1.3.3. One-third-octave-band Analysis .......................................................................................... 4 1.4. Frequency Weighting ................................................................................................................... 6 1.4.1. Type I (M-weighting) Marine Mammal Frequency Weighting ............................................. 6 1.4.2. Type II Marine Mammal Frequency Weighting ................................................................... 7 1.4.3. Audiogram Weighting ......................................................................................................... 9 1.5. Sound Level Thresholds Criteria ................................................................................................. 11 1.5.1. Injury Assessment ............................................................................................................. 11 1.5.2. Behavioural Assessment ................................................................................................... 12 2. METHODS ............................................................................................................................. 13 2.1. Source Levels ............................................................................................................................. 13 2.1.1. Vessel Source Levels ........................................................................................................ 13 2.1.2. Side-scan Sonar ................................................................................................................ 15 2.1.2.1. Transducer Beam Theory ..................................................................................... 15 2.1.2.2. Rectangular Transducers ...................................................................................... 17 2.1.2.3. Multibeam Systems .............................................................................................. 18 2.1.2.4. Side-scan Sonar .................................................................................................... 18 2.2. Sound Propagation Model........................................................................................................... 19 2.2.1. Two Frequency Regimes: RAM vs. BELLHOP................................................................. 19 2.2.2. N×2-D Volume Approximation ......................................................................................... 20 2.2.3. Sampling of Model Results: Maximum-over-depth Rule ................................................... 22 2.3. Acoustic Impact Estimations ...................................................................................................... 22 2.3.1. Instantaneous Impact, Single Vessel .................................................................................. 23 2.3.2. Instantaneous Impact, Vessel Group .................................................................................. 23 2.3.3. Cumulative Acoustic Impact, 24 Hour Operations ............................................................. 23 2.4. Model Parameters ....................................................................................................................... 23 2.4.1. Bathymetry ....................................................................................................................... 23 2.4.2. Geoacoustic Properties ...................................................................................................... 24 2.4.3. Sound Speed Profiles ........................................................................................................ 26 2.4.4. Geometry and Modelled Volumes ..................................................................................... 27 3. MODELLED SCENARIOS ........................................................................................................ 28 3.1. Sites ........................................................................................................................................... 28 3.2. Single Vessel Scenarios .............................................................................................................. 28 3.3. Vessel Groups ............................................................................................................................ 29 ii Version 1.0 JASCO APPLIED SCIENCES South Stream Pipeline – Russian Sector – Underwater Sound Analysis 3.3.1. Scenario 1: Dredging of Microtunnel Exit Pit and Transition Trench at Site 1.................... 30 3.3.2. Scenario 2: Stationary Pipe-laying at Site 1 ....................................................................... 30 3.3.3. Scenario 3: Pipe-laying with Active Anchor Handling at Site 1 ......................................... 31 3.3.4. Scenario 4: Pipe-laying with Dynamic Positioning at Site 2 ............................................... 32 3.3.5. Scenario 5: Pipe-laying with Anchor Handling Tugs at Site 2 ............................................ 32 3.3.6. Scenario 6: Crew Change (Pipe-laying) at Site 2 ............................................................... 33 3.3.7. Scenario 7: Dredging for Free Span Correction at Site 2 .................................................... 34 3.3.8. Scenario 8: Rock Dumping for Cable Crossings at Site 2 ................................................... 34 3.3.9. Scenario 9: Pipe-laying at Site 3 ........................................................................................ 35 3.3.10. Scenario 10: Crew Change (Pipe-laying) at Site 3............................................................ 35 3.4. Cumulative ................................................................................................................................. 36 3.4.1. Scenario C1: Nearshore Pipeline Section ........................................................................... 37 3.4.2. Scenario C2: Shelf Break .................................................................................................. 38 3.4.3. Scenario C3: Deep Sea ...................................................................................................... 38 4. RESULTS ............................................................................................................................... 40 4.1. Single-Vessel Instantaneous Sound Fields .................................................................................. 40 4.1.1. Vessels Operating at Shallow Water Site (S01) ................................................................. 40 4.1.2. Vessels Operating at Mid-water Site (S02) ........................................................................ 42 4.1.3. Vessels Operating at Deep Water Site (S03) ...................................................................... 45 4.2. Side-Scan Sonar ......................................................................................................................... 48 4.3. Vessel Group Instantaneous Sound Field .................................................................................... 55 4.3.1. Scenario 1: Dredging of Microtunnel Exit Pit and Transition Trench ................................