Maersk Oil Esia-16 Non-Technical Summary – Esis Tyra
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Intended for Maersk Oil Document type Non-Technical Summary (NTS) Date September 2015 MAERSK OIL ESIA-16 NON-TECHNICAL SUMMARY – ESIS TYRA Non-Technical Summary – ESIS Tyra 1 of 11 PREFACE This document is the Non-Technical Sum- mary (NTS) of the Environmental and So- 1. INTRODUCTION cial Impact Statement (ESIS) for the TYRA project . The NTS outlines in non-technical Maersk Oil is the operator of 15 oil and gas fields in the language the findings of the ESIS. Danish sector of the North Sea. The facilities are con- The ESIS is supported by seven generic nected by subsea pipelines through which the pro- technical sections describing the expected duced oil and gas are transported for processing on activities for the TYRA project (seismic, Dan, Gorm, Halfdan, Harald and Tyra, before being pipelines and structures, production, drill- sent onshore via Gorm and Tyra. Maersk Oil and A.P. ing, well stimulation, transport and de- Møller-Mærsk have the license to conduct oil and gas commissioning) . exploration and production in Denmark until 2042. The ESI S and associated generic technical Maersk Oil is the operator. sections for TYRA are available at DEA’s website www.ens.dk. In connection with the ongoing and future oil and gas activities by Maersk Oil in the Danish North Sea, an Environmental and Social Impact Assessment (ESIA- CONTEN TS 16) has been prepared. The overall aim of the ESIA-16 is to identify the likely significant environmental and social impact of Maersk Oil projects. 1. Introduction 2. The TYRA project The ESIA-16 covers the remaining lifetime of the ongo- 2.1 Overview ing projects and the entire life time for planned pro- 2.2 Existing facilities jects i.e. from exploration to decommissioning. The 2.3 Ongoing projects and planned devel- ESIA-16 consists of five independent Environmental opment and Social Impact Statements (ESISs) for the DAN, 2.4 Accidental events GORM, HALFDAN, HARALD and TYRA projects. 3 Environmental assessment 3.1 Environmental baseline The ESISs shall replace the Environmental Impact As- 3.2 Impacts from planned activities sessment conducted in 2010 “Environmental impact 3.3 Transboundary impacts assessment from additional oil and gas activities in the 3.4 Natura 2000 screening North Sea, July 2011” which is valid for the period 1 4 Social assessment January 2010 to 31 December 2015. 4.1 Social baseline 4.2 Impacts from planned activities 5. Impacts from accidental events 6. Mitigation 7. Conclusions REFERENCES Maersk Oil, “Maersk Oil ESIA-16, Environ- mental and Social impact statement – TYRA” , August, 2015. EDITOR Ramboll – www.ramboll.dk Revision: 1 Date: 2015-09-01 Doc.no.: ROGC-S-RA-000237 Figure 1-1 Maersk Oil North Sea projects TYRA, HARALD, DAN, GORM and HALFDAN. Non-Technical Summary – ESIS Tyra 2 of 11 Figure 1-2 Overview of existing TYRA facilities (not to scale) The purpose of the ESIS is to document the Existing facilities and planned activities assessment of the potential impacts from as well as potential accidental events exploration, production and decommission- Methodology used for the assessments ing on relevant environmental and social Environmental and social baseline receptors (e.g. water quality, marine mam- Environmental and social impact as- mals, employment, fishery). sessment for planned activities and acci- dental events The ESIS for the TYRA project covers the Mitigating measures activities related to ongoing and planned Transboundary impacts projects for the main processing and produc- Natura 2000 screening tion facilities Tyra East and West and the satellite platforms Tyra South East, Valde- A distinction is made in the ESIS between mar (A and B), Roar and Svend. An over- impact as a consequence of planned activi- view of the existing pipelines and structures ties and impact as a result of accidental for the TYRA project1 is provided in Figure events. 1-2. The responsible authority is the Danish En- The ESIA-16 has been made in accordance ergy Agency (DEA). with Executive Order no. 632 of 11/06/2012 on Environmental Impact Assessment (EIA). The present document is the Non-Technical The ESIS includes a comprehensive descrip- Summary (NTS) of the ESIS for the TYRA tion of: project. 1 “TYRA project” refers to the project, while “Tyra” refers to the platform. The project takes the name from the main processing facility. Non-Technical Summary – ESIS Tyra 3 of 11 2. THE TYRA PROJECT 2.2 Existing facilities Tyra East consists of six platforms and Tyra 2.1 Overview West consists of five platforms. The plat- The TYRA facilities are located in the Danish forms on Tyra East and Tyra West, respec- part of the central North Sea, approx. 230 tively, are connected by bridges, where all km west of Esbjerg on the west coast of interconnecting pipes and services are run. Jutland, Denmark. Continuous control and monitoring of the The TYRA project includes the main pro- satellite platforms Tyra South East, Roar, cessing and production facilities Tyra East Valdemar and Svend is carried out remotely and West and the satellite platforms Tyra from Tyra East and West. South East, Valdemar (A and B), Roar and Svend, which are connected by subsea pipe- In addition, the Tyra East and West plat- lines (Figure 1-2). forms form the export centre for all gas pro- duced by Maersk Oil in Denmark. The TYRA production was initiated at Tyra in 1984, Valdemar in 1993, Roar in 1996, The processing facilities include hydrocarbon Svend in1996 then later at Tyra South East processing equipment (oil, gas and produced in 2002. The total annual TYRA hydrocarbon water separation) and critical safety systems production peaked in 2005 and has been on such as an emergency shutdown system, a natural decline since. emergency blow-down system, fire and gas detection system and firewater system. In 2014, the annual hydrocarbon production at TYRA was 9.5 million barrels of oil (i.e. 2.3 Ongoing projects and planned 1.5 million m3) and 73 billion standard cubic development feet of gas (2 billion m3). In total, more than Several activities are planned for TYRA to 338 million barrels of oil and 4,420 billion continue and optimise the ongoing produc- standard cubic feet of gas have been pro- tion and potentially access new hydrocarbon duced from TYRA since 1984. resources. TYRA EAST TYRA WEST Accommodation Bridges Accommodation Bridges 96 beds four bridges connect the 80 beds four bridges connect the platforms (approx. 100 m platforms (approx. 100 m Helicopter deck long) and have walkways Helicopter deck long) and have walkways yes on one level. The TEFA yes on one level. The TWEA bridge module has three bridge module has four deck levels and is approx. deck levels and is approx. Platforms 65 m long Platforms 72 m long two wellheads (TEB, TEC), two wellheads (TEB, TEC), one process module and one process module and accommodation (TEA), one accommodation (TEA), one gas flare stack (TED) and gas flare stack (TED) and one riser platform (TEE) one riser platform (TEE) Non-Technical Summary – ESIS Tyra 4 of 11 Seismic data acquisition. Seismic investi- starts with hammering (driving) a conductor gations provide information to interpret the into the seabed. During drilling, Maersk Oil geological structure of the subsurface and to uses drilling mud to lubricate and cool drill identify the location and volume of remain- bits. The mud also has safety functions such ing and potential new hydrocarbon reserves. as preventing a well blowout. Following strict Seismic data is also acquired as part of drill- environmental guidelines, water-based drill- ing hazard site surveys and as part of sea- ing mud and cuttings consisting of rock bed and shallow geophysical surveys to map drilled from the well are discharged into the conditions for the design and installation of sea. In some occasions, oil-based mud can pipelines, platforms and other structures. be used and the mud and cuttings are brought onshore to be dried and incinerated. Pipelines and structure. Up to four well- head platforms (up to 60 well slots) con- Well stimulation. Well stimulation is per- nected by pipelines to the Valdemar platform formed to improve the contact between the may be installed. Furthermore, up to four well and the reservoir, thereby facilitating wellhead platforms (up to 36 well slots) hydrocarbon extraction for a production well connected by pipelines to the Tyra platform and water injection for an injection well. may be installed. Finally, a wellhead plat- Well stimulation is performed by creating form (10 well slots) connected by pipeline to fractures and cracks in the rock, which are the Svend platform may be installed. induced by acid stimulation or acid fractur- ing. In some of the new projects, it may be Regular maintenance will be undertaken necessary to use sand fracturing which con- including visual inspections and internal sists of adding sand (proppant) to the mix- cleaning of pipelines. ture. Most of the chemicals and proppant remain in the formation. The stimulation Production. The production at TYRA is com- fluid left in the well will be discharged to sea ing from mature fields. This means that oil whereas the proppant will be collected. and gas production is declining while the water production is increasing. This makes Transport. Personnel and cargo are trans- the separation of the fluids extracted from ported to the facilities daily via helicopters to the reservoirs (oil, water and gas) more support production and drilling operations. challenging. Chemicals are used to effective- Vessels may be employed in connection with ly and safely process and separate the hy- drilling and other work. drocarbons from the produced water. A frac- tion of the oil and chemicals, which is con- Decommissioning.