Intended for Maersk Oil Document type Non-Technical Summary (NTS) Date September 2015 MAERSK OIL ESIA-16 NON-TECHNICAL SUMMARY – ESIS HALFDAN Non-Technical Summary – ESIS HALFDAN 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 HALFDAN project. The NTS outlines in non- Maersk Oil is the operator of 15 oil and gas fields in the technical language the findings of the Danish sector of the North Sea. The facilities are con- ESIS. nected by subsea pipelines through which the pro- The ESIS is supported by seven generic duced oil and gas are transported for processing on technical sections describing the expected Dan, Gorm, Halfdan, Harald and Tyra, before being activities for the HALFDAN project (seismic, sent onshore via Gorm and Tyra. Maersk Oil and A.P. pipelines and structures, production, drill- Møller-Mærsk A/S have the license to conduct oil and ing, well stimulation, transport and de- gas exploration and production in Denmark until 2042. commissioning) . Maersk Oil is the operator. The ESI S and associated generic technical sections for HALFDAN are available at In connection with the ongoing and future oil and gas DEA’s website www.ens.dk. activities by Maersk Oil in the Danish North Sea, an Environmental and Social Impact Assessment (ESIA- 16) has been prepared. The overall aim of the ESIA-16 CONTEN TS is to identify the likely significant environmental and social impact of Maersk Oil projects. 1. Introduction The ESIA-16 covers the remaining lifetime of the ongo- 2. The HALFDAN project ing projects and the entire life time for planned pro- 2.1 Overview jects i.e. from exploration to decommissioning. The 2.2 Existing facilities ESIA-16 consists of five independent Environmental 2.3 Ongoing projects and planned devel- and Social Impact Statements (ESISs) for the DAN, opment GORM, HALFDAN, HARALD and TYRA projects. 2.4 Accidental events 3 Environmental assessment The ESISs shall replace the Environmental Impact As- 3.1 Environmental baseline sessment conducted in 2010 “Environmental impact 3.2 Impacts from planned activities assessment from additional oil and gas activities in the 3.3 Transboundary impacts North Sea, July 2011”, which is valid for the period 1 3.4 Natura 2000 screening January 2010 to 31t December 2015. 4 Social assessment 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 – HALFDAN”, August, 2015. EDITOR Ramboll – www.ramboll.dk Revision: 2 Date: 2015-09-15 Figure 1-1 Maersk Oil North Sea projects TYRA, HARALD, Doc.no.: ROGC-S-RA-000236 DAN, GORM and HALFDAN. Non-Technical Summary – ESIS HALFDAN 2 of 11 Figure 1-2 Overview of existing HALFDAN 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 HALFDAN project covers Mitigating measures the activities related to ongoing and planned Transboundary impacts projects for the Halfdan facilities (A and B) Natura 2000 screening and the satellite platform Halfdan C. An overview of the existing pipelines and struc- A distinction is made in the ESIS between tures for the HALFDAN project1 is provided in impact as a consequence of planned activi- Figure 1-2. ties and impact as a result of accidental events. The ESIA-16 has been made in accordance with Executive Order no. 632 of 11/06/2012 The responsible authority is the Danish En- on Environmental Impact Assessment (EIA). ergy Agency (DEA). The ESIS includes a comprehensive descrip- tion of: The present document is the Non-Technical Summary (NTS) of the ESIS for the HALFDAN project. 1 “HALFDAN project” refers to the project, while “Halfdan” refers to the specific platform. The project takes the name from the main processing facility. Non-Technical Summary – ESIS HALFDAN 3 of 11 2. THE HALFDAN 2.2 Existing facilities PROJECT Halfdan A comprises a combined wellhead and processing platform (HDA), one accom- 2.1 Overview modation platform (HDB) and a gas flare The HALFDAN facilities are located in the stack (HDC). South-Western part of the Danish sector of the North Sea, approx. 210 km west of Es- Halfdan B comprises a processing platform bjerg on the west coast of Jutland, Den- (HBD), a wellhead platform (HBA), a com- mark. bined riser and wellhead platform (HBB) and an accommodation platform (HBC). The HALFDAN project includes the main processing and production facilities Halfdan Halfdan C is an unmanned wellhead platform A and Halfdan B and the satellite production (HCA). Continuous control and monitoring of platform Halfdan C. The platforms are con- the HCA is carried out remotely from nected by subsea pipelines, through which Halfdan B. oil, gas and water are transported between the HALFDAN facilities and to Gorm and Tyra The processing facilities include hydrocarbon for further processing and export to shore processing equipment (oil, gas and produced (Figure 1-2). water separation) and critical safety systems such as an emergency shutdown system, The HALFDAN production was initiated at emergency blow-down system, fire and gas Halfdan A in 1999, then later Halfdan B in detection system and firewater system. 2004 and Halfdan C in 2007. The total an- nual production for the HALFDAN project is 2.3 Ongoing projects and planned now on a natural decline. development Several activities are planned for HALFDAN In 2014, the annual hydrocarbon production to continue and optimise the ongoing pro- at HALFDAN was 22.9 million barrels of oil duction and potentially access of new hydro- 3 (i.e. 3.7 million m ) and 46 billion standard carbon resources. 3 cubic feet of gas (1.3 billion m ). In total, more than 428 million barrels of oil and Seismic data acquisition. Seismic investi- 1,001 billion standard cubic feet of gas have gations provide information to interpret the been produced from TYRA since 1999. geological structure of the subsurface and to HALFDAN A HALFDAN B HALFDAN C Accommodation Accommodation Accommodation 32 beds 80 beds unmanned satellite Helicopter deck Helicopter deck Helicopter deck yes yes no Wells Wells Wells 35 37 9 Platforms Platforms Platforms one combined process module one process module (BD), two one wellhead (CA) and wellhead (DA), one wellheads (BA, BB) and one accommodation (DB) and one accommodation (BC) Bridges flare tower (BC) none Bridges Bridges connect the platforms (approx. connect the platforms (approx. 100 m to 140 m long) and have 100 m long) and have walkways walkways on two levels on two levels Non-Technical Summary – ESIS HALFDAN 4 of 11 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. One development project is being considered for HALFDAN, Well stimulation. Well stimulation is per- including possible drilling of up to 5 new formed to improve the contact between the wells from the existing platform (BB) or well and the reservoir, thereby facilitating possible installation of up to two new satel- hydrocarbon extraction for a production well lite unmanned platforms (with 10 well slots and water injection for an injection well. each) and multiphase, water injection and Well stimulation is performed by creating gas lift pipelines to Halfdan BD or Halfdan fractures and cracks in the rock, which are DC. induced by acid stimulation or acid fractur- ing. Most of the chemicals remain in the Furthermore, regular maintenance will be formation, but simulation fluid left in the undertaken including visual inspections and well will be discharged to sea. internal cleaning of pipelines. Transport. Personnel and cargo are trans- Production. The production at HALFDAN is ported to the facilities daily via helicopters to coming from mature fields. This means that support production and drilling operations. oil and gas production is declining while the Vessels may be employed in connection with water production is increasing. This makes drilling and other work. the separation of the fluids extracted from the reservoirs (oil, water and gas) more Decommissioning. The timing of decom- challenging. Chemicals are used to effective- missioning of the HALFDAN facilities is not ly and safely process and separate the hy- decided. Decommissioning will be done in drocarbons from the produced water. A frac- accordance with technical capabilities, indus- tion of the oil and chemicals, which is con- try experience and under the legal frame- tained in the treated produced water from work at the time of decommissioning. The the HALFDAN project, is discharged to sea at general approach is anticipated to be: wells Halfdan A and B. will be plugged and casing above seabed removed, platform facilities and jackets will The use and discharge of production chemi- be cleaned, removed and brought to shore, cals require approval form the Danish Envi- pipelines will be cleaned and left in place.