CROWES FOOT 3D SEISMIC SURVEY OTWAY BASIN

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1 CROWES FOOT 3D SEISMIC SURVEY OTWAY BASIN A modern 3D Seismic Vessel March 2015 Origin Energy is currently preparing an Environment Plan to support a proposed three dimensional ( 3D ) seismic survey in the Otway Basin. The proposed Crowes Foot 3D survey area is located approximately 15 km south-west of Cape Otway and 67 km north-west of King Island. The survey could potentially identify reserves to provide future gas supplies. Modern seismic surveys are a noninvasive technique commonly used for gas exploration to provide images of the subsea. Sound waves from an acoustic source are transmitted into the structures below the seabed and are reflected back like echoes. The reflected sound is measured by sensitive hydrophones on towed streamer cables. The data is then analysed by geoscientists who produce computer models of the different structures below the surface. If, as a result of the survey, there appears to be potential for commercial gas resources, additional regulatory approvals would be required before any further exploration or development activities could commence. SHALLOW DEEP Example of computer-generated image produced from seismic data

2 This map shows the expected surveying and operational area of the seismic vessel during normal operations, including turning areas. Support vessels will operate both inside and outside this area.

3 PROJECT OVERVIEW Location The proposed survey area is located in exploration permit VIC/P69 in the Otway Basin. The exploration area is approximately 950 square kilometres and is situated to the northeast of the existing Thylacine production platform which provides gas via a seabed pipeline to the onshore Otway Gas Plant near Port Campbell. The permit area is sited in water depths of approximately metres. Survey method Based on Origin s experience in undertaking similar surveys in the Otway Basin in the past, the most appropriate method to carry out this proposed survey is to use a multi-streamer vessel. Towed marine streamers would enable the survey to be completed within a shorter timeframe than other survey methods so that we can minimise impact on other users in the area. The seismic survey vessel will be supported by a dedicated offshore supply vessel assisting with marine traffic management and emergency response. There may also be a smaller guard vessel to liaise with local commercial and fishery operators in the vicinity and, if required, to move any entanglement hazards from the survey area. The final operational configuration, including the number of streamers, will be known once a suitable survey vessel is contracted and will be communicated to any impacted stakeholders ahead of the survey taking place. Timing Origin is planning to undertake the proposed survey in a period between 1 October 2015 and 31 January 2016, subject to receiving the required regulatory approvals and the engagement of a suitable contractor and vessel. The survey window has been identified based on existing knowledge of the marine environment, the potential impacts and associated mitigation strategies. The survey is likely to take up to six weeks to complete depending on seasonal marine weather conditions and the type of vessel used. Stakeholder feedback and environmental assessment, along with vessel availability, will further inform the timing of this survey within this window. Safety and environment Origin conducts all its gas exploration surveys in accordance with relevant safety and environmental approvals, using best industry practice. Origin has successfully and safely completed five seismic surveys in the region over the last five years. Origin recognises the Otway coast contains important ecosystems and heritage, social and economic values, and continues to support research in this region. Supporting this research helps to improve our understanding of the diverse ecosystems in the Otway Basin. Detailed operational planning will be conducted with consideration to relevant up-to-date marine, environmental and technical studies. As part of the planning for this survey, Origin is required to demonstrate to the regulator, the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA), that the proposed survey will meet strict environmental guidelines. We are currently preparing an Environment Plan which will be submitted to NOPSEMA. The Environment Plan is a comprehensive document that describes the existing environment and identifies how we will conduct all of the activities to avoid, minimise and manage any environmental risks. The Environment Plan will also show how Origin will meet all regulatory requirements. A summary of the Environment Plan will be made publicly available via the NOPSEMA website once accepted by the regulator. Consultation As part of our commitment to minimise the impact of our operations we are undertaking consultation with stakeholders regarding the proposed survey activity. Consultation with stakeholders on this project began in We will be re-engaging with these stakeholders and any other parties who may be relevant persons, as defined in the Environment Regulations. Relevant persons are those whose functions, interests and activities may be affected by the proposed Crowes Foot marine seismic survey. The purpose of the consultation is to confirm each stakeholder s connection or relationship to the proposed survey and seek their feedback based on relevant local knowledge and concerns, such as marine fauna and marine use (commercial and recreational) that we may need to address during our project planning. We will assess the merit of all feedback from stakeholders and the community, including any objections and claims, and provide responses where appropriate. Stakeholder feedback will be considered alongside a number of technical and environmental assessments as we prepare the Environment Plan.

4 FREQUENTLY ASKED QUESTIONS Will the survey activity be visible from the shore? Parts of the survey will be visible from the shore. It may be possible to see the survey vessel sailing backwards and forwards over the north of the survey area. Some of the smaller supporting vessels may also be seen from shore. We will provide further information to the community once we select the equipment for the survey and confirm the final configuration. Will the survey take place at day or night? The survey activity is a 24 hour operation. Will any equipment be left behind? All equipment is deployed from and towed behind the seismic vessel. There is no equipment placed in contact with the seabed. No equipment will be left behind. What happens if you discover gas? If as a result of the survey there appears to be potential for commercial gas resources, additional regulatory approvals will be required before drilling could commence. Why are you carrying out a survey here? We are exploring for natural gas. Over the past 30 years the industry has undertaken multiple surveys of the Otway Basin. This survey will supplement data and knowledge from previous surveys that will enable us to understand the geological structure of the rock formations beneath the survey area. The proposed survey could potentially identify new gas reserves. How long has Origin been using these survey techniques in the region? Origin has been operating in the Otway Basin since In 2013, Origin carried out the Astrolabe 3D Seismic Survey directly adjacent to the west of the proposed Crowes Foot 3D survey. The last 3D seismic survey conducted by Origin in the region was the Enterprise survey in November Have the potential impacts on marine life been considered? Yes, we have carried out an assessment of relevant studies and specialist advice on marine species and the marine environment. We are also continuing to consult a range of stakeholders, including local fishermen, regulatory bodies and groups with knowledge and expertise in the marine environment in this region, in the development of the Environment Plan. Have the potential impacts on whales been considered? Yes, we have taken into consideration advice from whale experts. All operations will be conducted in accordance with strict environmental management guidelines established by the Australian Government and international experts. All survey work will be conducted under the supervision of experienced Marine Mammal Observers who will have Origin s full authority to stop the survey should a whale appear nearby. What is an Environment Plan and who assesses it? The Environment Plan is a detailed document that describes the existing environment and any risks to the environment that the seismic survey may pose, along with all of the measures that will be implemented to avoid or minimise any risk of environmental harm. The plan shows how Origin will meet all regulatory requirements and contains all of the information needed to show how the environment will be protected during the survey. The Environment Plan will be assessed by NOPSEMA. After NOPSEMA have approved the Environment Plan, a summary of the plan shall be published on the NOPSEMA website. Will there be exclusion zones for other vessels around the survey area? The Australian Maritime Safety Authority will issue a Notice to Mariners to all other vessels advising that they should avoid the survey area. Origin will maintain direct communications with professional fishers operating in the area before, during and upon conclusion of the survey. The guard and support vessels will communicate and liaise with water users about the operation, as required. During the survey, if other vessels are sighted, standard maritime protocols and precautions will be in place to provide adequate distance to avoid nets and lines and vessel collisions. When will work start and finish? The survey is proposed to be undertaken between 1 October 2015 and 31 January The survey is estimated to take up to six weeks to complete depending on seasonal marine weather conditions, including predicted down-time due to adverse weather conditions typical of the Otway region. CONTACT US For more information visit Origin invites feedback from stakeholders potentially affected by the proposed Crowes Foot 3D seismic survey including those stakeholders with specific local knowledge and/or an interest in the environmental performance of these projects. Feedback will inform the development of the Environment Plan and can be provided by contacting: Linda French Community Relations Specialist Phone: community.team@ originenergy.com.au Please be advised that stakeholder feedback will be communicated to NOPSEMA as required by legislation.

5 INFORMATION REGARDING DIVING ACTIVITY CROWES FOOT 3D SEISMIC SURVEY OTWAY BASIN Sound created by marine seismic surveys Marine seismic surveys use acoustic energy to map geological structures in the subsurface. This acoustic energy results in the transmission of acoustic waves through the water. It is experienced by humans as noise, which may sound like a low frequency rumble or pulse. There is already significant ambient noise in the ocean, generated by wind, waves, marine life and shipping vessels. The sound from seismic sources can be above typical background ambient noise in the ocean. However, the intensity of sound from seismic surveys decreases as it spreads away from the source of the sound. This is called attenuation. The rate of attenuation is influenced by many different factors including: water layers and thermoclines sea state including ocean temperature, swell, currents, tides, and wave action sea floor properties, including types of rocks, structures and bathymetry. Diving activity Human exposure to any elevated sound levels over an extended period of time may lead to hearing damage. Divers in the vicinity of a seismic survey who spend extended periods of time underwater may be exposed to the sound from the seismic survey. Origin has carried out detailed planning to identify and engage with people who may carry out professional or recreational diving activity within the proposed Crowes Foot survey area and up to 10 km from the survey area. Sound in near-shore areas From our experience with measuring acoustic sound during seismic surveys in the Otway Basin, we know that seismic sound is attenuated quicker in near-shore waters than in other areas. This is due to the rugged seafloor with calcarenite substrate (a type of soft limestone) that attenuates acoustic energy that would otherwise be reflected back into the water column and continue as noise. Diagram is for illustration purposes only not to scale May 2015

6 Plan for safe diving activity Even though the acoustic sound will be substantially attenuated in the near-shore areas around the proposed Crowes Foot survey, Origin will take a conservative approach to planning its operations and any diving activity that may occur at the same time as the survey. Our approach will vary depending on the distance of the diving activity from the acoustic source during the survey. Diving within 10 km The focus of detailed planning for safe diving activity that may occur during the proposed Crowes Foot survey will be on professional commercial divers and abalone divers. Origin will consult with divers planning to operate at the same time as the survey to jointly develop a plan that assesses any risks, prioritises activities and minimises or eliminates simultaneous seismic and diving activities. A daily work plan will be developed to ensure regular communications and safe commencement or continuation of all seismic survey activity. Diving within 5 km Planning will occur as above and continuous communications will be maintained with any diving parties. Diving within 3 km Planning will occur as above and diving must not occur during seismic survey activity unless an alternative plan is developed after testing of the acoustic source. Recreational diving from the shore For recreational diving activity close to the shore, the seismic acoustic pulse may be heard, particularly if the weather and sea is calm and the survey vessel is travelling in the northern areas of the proposed survey area. However, given the sound attenuation described above, we do not expect any hearing impact for recreational shore divers. Nevertheless, signage will be placed at common shore entry points for recreational diving. The signs will explain the Crowes Foot survey activity, dates, locations, advice to divers and a contact number to call for further information. Contact us Linda French Community Relations Specialist Phone: community.team@originenergy.com.au Please be advised that stakeholder feedback will be communicated to National Offshore Petroleum Safety and Environment Management Authority (NOPSEMA) as required by legislation.