Enquest Heather Limited Galia Field Development Environmental Statement
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EnQuest Heather Limited Galia Field Development Environmental Statement DECC Document Ref: D/4127/2011 EnQuest Heather Limited Document Ref: TBC ISSUED: 02 MAY 2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT STANDARD INFORMATION SHEET Project Name Galia Field Development DECC Reference D/4127/2011 Number Type of Project Small oil field development Undertaker Name EnQuest Heather Limited Undertaker 5 Floor Consort House, Stell Road, Aberdeen, AB11 5QF, United Kingdom Address Licencees / EnQuest Heather Limited (100%) Owners EnQuest Heather Limited wishes to redevelop the Duncan field in UK continental shelf (UKCS) Block 30/24 in the Central North Sea (CNS). The field, to be renamed Galia, will consist of one production well tied-back via a new oil production flowline to the Alma production manifold. Which is turn is tied-back to the EnQuest Producer (formerly known as the Uisge Gorm) floating production, offloading and storage facility (FPSO). This ES covers the drilling of a single production well, installation of a short tie back to the Alma production manifold and subsequent production via the FPSO. The well will be drilled using a combination of water and oil based muds. Cuttings and water based muds will be discharged to sea both at the seabed and from the drilling rig to the sea surface. Oil based mud and cuttings will not be discharged and will be skipped and shipped back to shore for disposal. The flowline, umbilical and power cable will be trenched between the well and the Alma production manifold. Concrete mattresses will be used for protection. There will Short Description be no rock dumping at Galia. Produced crude will be collected from the FPSO by shuttle tanker once every two weeks. The majority of the produced gas will be used for power generation, however there will be a period during the early part of field life where excess gas is produced that cannot be burned, this will be flared. Under normal conditions there will be no overboard discharge and as noted above, water quality could only be affected during occasional outage of the PWRI onboard the FPSO or as a result of production (from all wells) starting prior to the commissioning of the injection wells. Current estimates are that, based on a 10 year field life, the base case recovery from the Galia field will be 1.144 million tonnes (1.37 million m3) with a high recovery case of 1.42 million tonnes (1.7 million m3). Dual electrical submersible pumps (ESP) will be utilised at Galia to maximise production. Construction is scheduled to start in September 2012. First oil is anticipated in October 2013. Anticipated Start September 2012 of Works Previous / Other Statements Alma Field Development Environmental Statement (D/4110/2011) Related to this Project REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT EnQuest is aiming to limit environmental effects to low impact through project design, mitigation measures and operational controls. No impacts associated with the development have been categorised as Major or Critical, meaning that the majority of the impacts were assessed as having no or minor residual impact (i.e., impacts can be managed through effective standard operating procedures). During construction and production it is considered that the following activities may Significant have an impact: on the environment: atmospheric emissions; anchoring of the drilling Environmental rig; discharge of chemicals and drill cuttings; positioning of the well head, trenching; Impacts Identified concrete mattressing on the seabed; and the accidental spill of hydrocarbons and/or chemicals. However in all instances the severity of the impact is limited by the nature and composition of the environment and by the fact that these activities are short-term and affect a localised area. With mitigation measures in place, the Galia field development will have a minor impact on the environment. Statement Intertek METOC and EnQuest Heather Limited Prepared By REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT NON-TECHNICAL SUMMARY INTRODUCTION EnQuest Heather Limited is an independent oil and gas development and production company and operator of the Galia field in the UK Central North Sea (CNS), located in UKCS Block 30/24 in a water depth of approximately 80m. EnQuest Heather Limited plans to develop the Galia field through a single production well tied-back via a new production flowline, umbilical and power cable to the nearby Alma production centre, which is in turn tied back to the EnQuest Producer floating production, storage and offloading facility (FPSO). Oil production will be via the FPSO and export through the use of a shuttle tanker. In compliance with regulatory requirements, and to responsibly manage any impacts from the development, EnQuest has carried out an Environmental Impact Assessment (EIA) of the proposed development. The EIA process establishes the environmental baseline in the area of the proposed development and identifies environmental sensitivities, particularly with relevance to the concerns of stakeholders and regulatory bodies. It also evaluates relevant environmental impacts and their significance, and finally proposes mitigation measures which the operator will implement to minimise these impacts. This document reports on the EIA process, its findings and conclusions. GOVERNING LEGISLATION Offshore oil and gas developments are governed by a framework of International, European Community (EU) and UK laws, policies and guidelines. These dictate the management goals and objectives which an environmental assessment may aim to achieve. The main UK regulations that apply to the project are: Petroleum Act 1998 – Requires all offshore oil and gas development to apply for consent to undertake the project. Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007 – These regulations implement the European Commission (EC) EIA Directive (97/11/EC) and Public Participation Directive (2003/35/EC), and require an Environmental Statement (ES) to be submitted for offshore oil and gas projects and public participation in the consent process. Offshore Marine Conservation (Natural Habitats, &c.) Regulations 2007 (as amended in 2009 and 2010) – These regulations implement in the UK the EC Habitats REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT Directive (92/43/EC) and the EC Birds Directive (79/409/EC) and aim to protect marine species and wild birds from environmentally damaging activities. It is now an offence under the Regulations to physically injure or deliberately disturb wild animals of a European Protected Species. Offshore Petroleum Activities (Conservation of Habitats) Regulations 2001 (amended in 2007) – The regulations apply the EC Habitats and EC Birds Directives in relation to oil and gas projects on the UKCS. PROJECT JUSTIFICATION Three quarters of the UK’s current primary energy is met by oil and gas. In 2010, oil produced on the UKCS satisfied 87% of domestic demand. In 2020, it is estimated that 70% of primary energy consumed in the UK will still come from oil and gas, even upon the achievement of the Government’s target to source 15% of energy from renewable sources. If investment is sustained, the UKCS has the potential to satisfy around 60% of the UK’s oil and gas demand in 2020 (OGUK 2011). In 2000, the UK Government identified the need to stimulate oil and gas investment and activity to ensure that indigenous production of oil and gas remained at significant levels into the future. The Promote UK campaign is designed to attract new entrants onto the UKCS, and focused on: Independent oil companies with the resources to drill wildcat exploration wells and exploit the full value chain from exploration to development; and Niche ‘developers’, particularly those with the skills to develop previously undeveloped discoveries by using technically innovative and best cost solutions (DECC 2011a). As a result of these initiatives, EnQuest has been active on the UKCS since 2010. It specialises in predominantly mature areas of the NNS and CNS, aiming to maximise the potential from existing fields and future developments in the UKCS. The longer term strategy is to become a prominent exploration and development operator. The Galia Field development is part of this strategy and fits many of the UK energy policy objectives: It is an economically viable development that has been designed to maximise reserve recovery within an existing mature province using best cost solutions It is a national resource that will help to contribute towards energy security PROJECT ALTERNATIVES The consideration of alternatives to a proposed project is a requirement of the Offshore Petroleum Production and Pipelines Regulations. A comparison of alternatives helps to determine the best method of achieving the project by indicating the best available REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT technology (BAT) or the best environmental practice (BEP) or at the very least the option which minimises environmental impacts. Alternatives to the proposed project have been considered. The Galia field is a re- development of an existing oil field and is not within a zone designated as a currently feasible site for an alternative offshore energy technology such as wind. As such, the development for hydrocarbon development is considered to be the best option for providing a new energy source. EnQuest has investigated a range of hydrocarbon development options taking into account technical, environmental and economic factors, which are summarised below. Given the compact nature of the field and relatively short field life, the decommissioning strategy has played an important role in option selection (for further details see Section 3.2, Table 3-2). PRODUCTION SYSTEM Options: Tie in to Alma development & use of EnQuest Producer FPSO, or Provision of own production facilities Tie in to Alma development & use of EnQuest Producer FPSO was selected as the best production option.