Taranaki West 3D Seismic Survey MMIA Marine Mammal Impact Assessment Report Number 740.10034 16 November 2016 PGS Australia Pty Ltd Level 4, IBM Centre 1060 Hay Street West Perth WA 6005 Australia Version: v2.1 PGS Australia Pty Ltd Report Number 740.10034 Taranaki West 3D Seismic Survey MMIA 16 November 2016 Marine Mammal Impact Assessment v2.1 Page 2 Taranaki West 3D Seismic Survey MMIA Marine Mammal Impact Assessment PREPARED BY: SLR Consulting NZ Limited Company Number 2443058 5 Duncan Street Port Nelson 7043, Nelson New Zealand (PO Box 5061, Port Nelson 7043 Nelson New Zealand) T: +64 274 898 628 [email protected] www.slrconsulting.com This report has been prepared by SLR Consulting NZ Limited with all reasonable skill, care and diligence, and taking account of the timescale and resources allocated to it by agreement with the Client. Information reported herein is based on the interpretation of data collected, which has been accepted in good faith as being accurate and valid. This report is for the exclusive use of PGS Australia Pty Ltd. No warranties or guarantees are expressed or should be inferred by any third parties. This report may not be relied upon by other parties without written consent from SLR. SLR disclaims any responsibility to the Client and others in respect of any matters outside the agreed scope of the work. DOCUMENT CONTROL Reference Status Date Prepared Checked Authorised 740.10034 v2.1 16 November 2016 Helen McConnell Dan Govier Dan Govier 740.10034 v2.0 2 November 2016 Helen McConnell Dan Govier Dan Govier 740.10034 v1.0 18 October 2016 Helen McConnell Dan Govier Dan Govier 740.10034 v0.2 28 July 2016 Helen McConnell Dan Govier Dan Govier 740.10034 v0.1 24 December 2015 Nicole Pannell Dan Govier Dan Govier Helen McConnell SLR Consulting NZ Limited PGS Australia Pty Ltd Report Number 740.10034 Taranaki West 3D Seismic Survey MMIA 16 November 2016 Marine Mammal Impact Assessment v2.1 Page 3 Executive Summary PGS Australia Pty Ltd (PGS) is proposing to acquire a three dimensional (3D) marine seismic survey in the Taranaki Basin. The Operational Area lies to the northwest of Cape Farewell in water depths of over 200 m. The seismic survey is predicted to be a 45 day operational programme that is scheduled to be acquired between approximately December 2016 and January 2017. The PGS Apollo will undertake the survey using an acoustic source volume of 3,660 in3. The seismic vessel will tow 10 streamers that extend 8.1 km behind the vessel and will be accompanied by a support vessel (Thor Alpha). This Marine Mammal Impact Assessment (MMIA) is a pre-requisite to seismic operations in New Zealand’s Exclusive Economic Zone (EEZ) which, under the EEZ (Environmental Effects) Act 2012 and the associated Permitted Activities Regulations stipulate mandatory compliance with the Department of Conservation’s 2013 Code of Conduct for Minimising Acoustic Disturbance to Marine Mammals from Seismic Survey Operations (the ‘Code of Conduct’). As well as compliance with the Code of Conduct, PGS will operate in accordance with relevant NZ legislation, international conventions and their internal environmental standards. This MMIA sets out to describe the seismic operations that PGS proposes to undertake, provide a description of the baseline environment, identify the actual and potential effects of the proposed operations on the environment and to specify the measures that PGS intends to take to avoid, remedy, or mitigate any potential adverse effects. An assessment of the significance of any potential effects is also provided through an Environmental Risk Assessment (ERA) process. The MMIA not only includes a discussion on the potential effects of seismic operations on the biological environment, but also on the social, cultural and commercial environments of the Operational Area. A significant part of the development of this MMIA was engagement with stakeholders through the provision of information sheets, letters and face-to-face meetings. Information collected during this engagement process was used to populate the MMIA and to refine survey design where possible. In assessing the baseline environment it was noted that the marine mammal species most likely to be present in the Operational Area are pygmy blue whales, humpback whales, sperm whales, common dolphin, long-finned pilot whales and killer whales. Of these species only the killer whale is considered to be threatened under the New Zealand Threat Classification System, and the Operational Area is not considered to be of particular ecological importance for killer whales which travel readily on a regional basis. The recent observation of feeding and breeding behaviour by pygmy blue whales in the South Taranaki Bight Region has been carefully considered in the development of this impact assessment. Acoustic disturbance from seismic surveys is considered to be the most significant potential effect from the Taranaki West 3D Seismic Survey. Hence compliance with the Code of Conduct is the primary mitigation measure that will be employed during the Taranaki West 3D Seismic Survey. Of primary importance is 1) the presence of marine mammal observers (MMOs) who visually and acoustically detect marine mammals, 2) delayed starts if marine mammals are detected in close proximity to the acoustic source before operations commence, 3) the use of ‘soft starts’ to ensure that any undetected marine mammals have an opportunity to leave the vicinity before full operational power is reached, and 4) shut downs of the acoustic source if marine mammals enter the defined mitigation zones. SLR Consulting NZ Limited PGS Australia Pty Ltd Report Number 740.10034 Taranaki West 3D Seismic Survey MMIA 16 November 2016 Marine Mammal Impact Assessment v2.1 Page 4 Executive Summary Although sound transmission loss modelling (STLM) is not required when a seismic survey is conducted outside an Area of Ecological Importance (defined by the Department of Conservation), PGS has elected to undertake this modelling as an additional component for the development of this MMIA. This modelling is used to predict how far sound from the seismic survey is predicted to travel underwater, and to assess the validity of the mitigation zones specified in the Code of Conduct (which are designed to protect marine mammals from behavioural and physiological effects associated with underwater noise). The results of the STLM indicate that the standard mitigation zones in the Code of Conduct will sufficiently protect marine mammals from both behavioural and physiological effects during the Taranaki West 3D Seismic Survey. In addition to compliance with the Code of Conduct PGS has committed to the following actions to avoid, remedy or mitigate potential adverse effects of the Taranaki West 3D Seismic Survey on the biological, social, cultural and commercial environment of the Operational Area: Seismic operations will continue around the clock (as possible) to reduce the overall duration of the survey; PGS has undertaken source modelling to ensure that their survey is using the lowest possible acoustic source volume while still ensuring the geological objectives of the survey can be fulfilled; PGS has undertaken STLM to confirm that the mitigation zones in the Code of Conduct are appropriate for this survey; Marine mammal sightings will be collected whilst in transit between the Operational Area and Port Taranaki; MMOs will be vigilant for entanglement incidents and will report any dead marine mammals observed at sea; MMOs will notify DOC immediately of any Hector’s/Maui’s dolphin sightings; Weekly MMO reports to be provided to the regulators; PGS will consider covering the cost of necropsies on a case-by-case basis in the event of marine mammal strandings; PGS will provide an opportunity for the participation of a trainee iwi MMO(s); Post-survey meetings with iwi groups will be convened to discuss any issues that may have arisen during the survey; PGS will provide a seafloor bathymetry image to fishing groups after data processing is complete; and Web-based near real-time vessel positioning updates will be provided to commercial fishers. In summary, the potential effects of the proposed seismic operations are considered to be appropriately managed by the mitigation measures noted above. On this basis it is considered that behavioural or physiological effects on marine mammals are unlikely, and that potential social, cultural and commercial impacts are also unlikely given the distance from shore and the limited number of regular users of this offshore area. SLR Consulting NZ Limited PGS Australia Pty Ltd Report Number 740.10034 Taranaki West 3D Seismic Survey MMIA 16 November 2016 Marine Mammal Impact Assessment v2.1 Page 5 TABLE OF CONTENTS 1 INTRODUCTION 9 1.1 Background 9 1.2 General Approach 11 1.3 Consultation 11 1.4 Research 13 2 PROJECT DESCRIPTION 14 2.1 Marine Seismic Surveys - overview 14 2.1.1 2D and 3D surveys 14 2.1.2 Underwater sound 14 2.1.3 The acoustic source 15 2.1.4 The streamers 16 2.2 Taranaki West 3D Seismic Survey 17 2.3 Navigational Safety 20 2.4 Survey design – Alternatives and Mitigations 20 3 LEGISLATIVE FRAMEWORK 21 3.1 Crown Minerals Act 1991 21 3.2 Marine Mammals Protection Act 1978 21 3.3 Exclusive Economic Zone & Continental Shelf (Environmental Effects) Act 2012 21 3.4 2013 Code of Conduct for Minimising Acoustic Disturbance to Marine Mammals from Seismic Survey Operations 22 3.4.1 Notification 23 3.4.2 Marine Mammal Impact Assessment 23 3.4.3 Areas of Ecological Importance