The Teak-Samaan-Poui marine ecosystem mapping study

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1 The Teak-Samaan-Poui marine ecosystem mapping study Teak-Samaan-Poui (TSP) Offshore Oil and Gas Production Block operated by Repsol E&P T&T Limited, Trinidad & Tobago Identification of the relevant tip(s) Tip 2: Assess sensitive areas Understand the location and significance of protected areas, endangered species, sensitive habitats and key natural resources. This is critical to the early selection of facility locations and a project s overall biodiversity action planning. It will help keep projects on track and limit impacts. Tip 10: Adapt and improve Integrate biodiversity into HSE Management Systems to assure the plan-do-check-act cycle is complete and that risks are addressed throughout the asset life cycle. From Repsol s, perspective applying Tip 10 allows the organization to effectively respond to feedback from monitoring and reporting activities, thereby adapting and improving mitigation and management approaches, compliance with legal requirements and stakeholder relations. Executive summary The Teak-Samaan-Poui (TSP) Block has been in existence since the late 1970s and is the largest offshore oil and gas exploration and production block located off the southeast coast of Trinidad. Repsol E&P T&T Limited (Repsol TT) took over the operations in November At that time there was very little emphasis placed on conducting research on the offshore marine environment. As such, very little was known about the marine habitats within the block and in the offshore marine waters of Trinidad & Tobago as a whole. This drove the decision for Repsol TT to undertake the TSP Ecosystem Mapping Project in October 2006 in response to the corporate launch of Repsol s Biodiversity Policy. This project was aimed at satisfying the Corporate Biodiversity Policy objective of integrating biodiversity into its management systems and decision-making processes, including environmental and social assessments Through a partnership with a local university, Repsol TT and M.Sc. and M. Phil. students are undertaking a series of surveys to map the physical and biological characteristics of the TSP Block. Thus far, the benthic fauna has been mapped; and at present, surveys are ongoing to map the presence and behaviours of marine birds and mammals. These surveys are aimed at mapping the physical and biological characteristics of the marine environment of the TSP Block to be able to differentiate between natural variations and anthropogenic activities. Figure 1. Repsol s Teak-Samaan-Poui Fields Background The TSP Block is comprised of three mature fields Teak, Samaan and Poui consisting of three production platforms, ten drilling satellites, one compression satellite and approximately one hundred active wells (Figure 1). The Biodiversity Management Plan (BMP) was designed to assist with decision-making for the continued operation and exploration of the block during its expected lifetime. Specific aims of the project were to: create a biological catalogue of the marine flora and fauna, and the habitats they occupy within the TSP Block; classify species and habitats on the basis of sensitivity, e.g. rare, threatened, endangered; or of commercial significance; provide a body of data to assist with meeting legal environmental compliance requirements; contribute to improving emergency response management of oil spill incidents, and enhance relations with community stakeholders. Biodiversity legal and policy framework in Trinidad and Tobago Trinidad and Tobago has signed six main international treaties and conventions that support biodiversity with The Convention on Biological Diversity being the most significant. At a national level, there are only a few key legislative and policy documents that seek to protect biodiversity through the regulation and management of anthropogenic activities.

2 The main ones include The Environmental Management Act 2000, Chapter 35:05 of the laws of Trinidad and Tobago, National Environmental Policy 2001, National Biodiversity Strategy and Action Plan, National Policy and Programmes on Wetlands and the Establishment and Management of a National Park System. Legislative and policy development for the protection and conservation of biodiversity in Trinidad & Tobago has focused on land-based aspects, including plants, birds, amphibians and a range of land mammals such as the howler monkey and ocelot. The exception has been the leatherback sea turtles, which visit many east coast beaches each year. In this context there was a clear need to gain an understanding of the biodiversity of offshore marine habitats. Management and protection of biodiversity The Repsol TT BMP project was launched in 2006 with a Needs Assessment Study. A comprehensive literature review identified data and information gaps and defined a scope for the BMP. This study found that the main threats to biodiversity in the marine environment include sediment, water and air pollution, unsustainable use of natural resources, alien and introduced species, oil and gas activities and other socio-economic activities such as fishing. However, the contributory impacts of each of these stressors remained unknown. Thirteen prospective projects were identified based on the Needs Assessment Study; the TSP Ecosystem Mapping Project was eventually selected as the BMP. This project intends to develop and continuously build a living map of the marine habitats and species within the TSP Block over the lifetime of its operations; with special focus on the marine seafloor sediment, water quality, marine mammals (cetaceans) and marine birds of the region (avifauna). Figure 2. QTC survey of the TSP Block The mapping surveys focused on collecting data on seafloor bathymetry (i.e. the contours of the seafloor) and the distribution of fauna there. Benthic organisms (those that live in or on the sea bottom) are an important building block of ecosystem sustainability and are likely to be early indicators of ecosystem stress (Figures 3 and 4). They are of particular interest to marine oil and gas operations because of the potential impacts of drill cuttings discharges (small rock fragments formed when Ecosystem mapping of the seafloor The ecosystem mapping activities commenced in 2007 with a comprehensive mapping study of the seafloor of the entire TSP Block (Figure 2). Quester Tangent Technology (QTC) was employed for its less invasive data collection features and high output mapping capabilities. QTC collects returning acoustic echoes reflected off the seabed in order to characterize habitats and near surface sediments and presents no contact with obstacles, pipelines, or harm to marine benthic and pelagic fauna. A wide number of different habitats (Freeman and Rogers, 2003), species (Freeman et al., 2004) and sediment types (Collins et al., 1998) have been reliably identified and mapped using QTC worldwide. Figure 3. Benthic fauna sample Nassariidae Family (Dog Whelks)

3 drilling through the Earth s crust to find oil or natural gas), e.g. smothering; and produced water discharges, e.g. toxicity effects. This phase of the TSP Ecosystem Mapping Project revealed that the TSP Block is broadly comprised of four distinct sediment and benthic habitat types (Table 1): Muddy clay. Sand with muddy shell fragments. Coarse sand and mud with fine shell. Coarse sand rubble and patchy reef. Figure 4. Benthic fauna sample Echinoderm (Brittle Star) The QTC assessment represented a significant step forward in understanding the TSP Block and how natural variations in parameters such as salinity, depth, bathymetry, ph and dissolved oxygen influence both the spatial and seasonal distribution of the flora and fauna found on the bottom, or in the bottom sediments (Figure 5). All four benthic communities were strongly associated with differences in the physical conditions of the Table 1. Sediment and Benthic Habitat Types in the TSP Block Sediment type Muddy clay Description Densely packed polychaete, Goneplacidae (crabs) and Ophuiroids (brittle stars) burrows Surface features and appearance Flat seabed with patchy fine sediment clumps. No light penetration, high turbidity and nutrient load Distribution in the TSP Block Characteristic of the southern region of the TSP Block Photograph Sand with muddy shell fragments Moderately dense covering of polychaete and crustacean burrows with dense colonies of brittle stars Undulating surface with some hydroid patches. Fine layer of muddy sediment with dense layers of detritus mats Dominates the northern region of the TSP Block; also occurs intermittently in the eastern regions Coarse sand and mud with fine shell Coarse sandy Rubble and patchy reef Small patches of polychaete and crustacean burrows and mounds Small colonies of hydroids and algal clumps with occasional sea fans, patches of soft/hard coral and sponge Undulating surface with sand ripples and step sided banks Moderately flat surface with small patches of boulders and shell fragments. Areas tidal swept, moderate structural complexity Characteristic of the central region of the TSP Block and appears to be strongly associated with a change in bathymetry that runs east-west and south-west across the block Occurs along the shallow west coastal waters of Trinidad known as the Tourmaline Shoals which is known to contain patchy coral reefs

4 Figure 5. Correlation between physical characteristics of the environment and the distribution of benthic communities across the TSP Block Figures 6-8. Marine avifauna and mammals observed in the TSP Block during the December 2011 survey magnificent frigate birds, brown booby, and Atlantic spotted dolphins)

5 Figure 9. TSP Biodiversity Wall Map (A Stakeholder Consultation Tool) environment such as depth, as well as physical conditions of the water column including salinity, dissolved oxygen and ph. The knowledge derived is useful in differentiating between variations that occur naturally and those that are caused by anthropogenic influences (e.g. seasonal variations in sediment loading versus drill cuttings deposition). Marine mammal and avifauna surveys These surveys are being undertaken as part of the TSP Ecosystem Mapping Project in partnership with a local university, with the first of the avifauna surveys completed in December Two local M.Sc. and M. Phil. students will be selected each year to participate in data collection surveys, which will contribute to the TSP Ecosystem Mapping Project while simultaneously providing students with opportunities to undertake high value and original research. Surveys are undertaken jointly with Repsol TT personnel under a joint supervision arrangement. Marine avifauna and marine mammal data analysis are ongoing. Thus far, fifteen species of avifauna have been recorded, including the magnificent frigate bird, brown boobies, and various species of shearwaters and petrels; and two species of marine mammals, the Atlantic spotted dolphins and bottlenose dolphins, have been observed (Figures 6-8). Going forward, these surveys will be undertaken in each of the two tropical seasons wet season from June to December and dry season from January to May to continue to gather data on species presence, abundance and behaviour. Communication and educational outreach The involvement of stakeholders has been an integral part of the BMP from its inception in A communicative tool in the form a Wall Map (Figure 9) was developed in 2008 to assist with sharing information on what had been discovered from the study up to that time. This tool is also used for ongoing stakeholder engagements and will be used in planned future phases of the BMP for engaging primary schools in the Mayaro-Guayaguyayare Region in the future. Integration of biodiversity into Repsol TT s decision-making process Repsol TT has already started reaping the benefits of including biodiversity into its HSE Management System and decision-making process. It is evident in various aspects of the plan-do-check-act cycle of its day-to-day operations, as well as in project management. Some specific areas of benefit to note are: The improved quality of data used to prepare applications for Environmental Permits and the

6 preparation of Environmental Impact Assessment studies. Specifically, the greater temporal and spatial spread of the dataset enables a more realistic assessment of changes to environmental conditions. Appropriate mitigation measures and more targeted monitoring plans are being developed and implemented through Environmental Management Plans. The information being gathered has also helped enhance the quality of information used for stakeholder consultations. New knowledge of commercially important areas of the TSP Block and the location of areas of ecological interest, e.g. the Tourmaline Shoals Contact details Ryan Ramjit, Regional HSE Manager, Repsol E&P T&T Limited, Repsol Tower, #4 Queen s Park West, Port-of- Spain, TRINIDAD & TOBAGO. Telephone (868) rramjitr@repsol.com Soriaya Manwaring, HSEMS Advisor, Repsol E&P T&T Limited, Repsol Tower, #4 Queen s Park West, Port-of- Spain, TRINIDAD & TOBAGO. Telephone (868) sbakshm@repsol.com Further reading Freeman S. M. and Rogers S. I. A (2003) New Analytical Approach to the Characterisation of Macroepibenthic Habitats: Linking Species to the Environment. Estuarine, Coastal and Shelf Science. 56: Freeman, S.M., Mackinson, S. and Flatt, R. (2004). Diel Patterns in the Habitat Utilisation of Sandeels revealed using Integrated Acoustic Surveys. Journal of Experimental Marine Biology and Ecology. 305: Collins, W.T., and McConnaughey, R.A. (1998). Acoustic Classification of the Sea Floor to address Essential Fish Habitat and Marine Protected Area Requirements. Canadian Hydrographic Conference (March 1998), CHS, Victoria, British Columbia, Canada. pp. 1-9.