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. For a small development with a relatively short field life such as Galia, the ability to utilise an existing production facility is a key factor - on both economic and environmental grounds.

The advantages of this option include: minimisation of seabed footprint due to the proximity of the Alma production centre; lower CAPEX and OPEX when compared with dedicated facilities and avoidance of environmental impacts associated with new build.

DRILLING RIG

Options: Semi submersible, or

Heavy duty jack up

A Semi submersible rig option was selected for the Galia well as the Ocean Princess semi submersible drilling rig will already be on location at the Alma field.

PRODUCTION FLOWLINES

Options: Trenched and buried, or

Surface laid and protected

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Trenched and buried was selected as this a proven method which provides the greatest protection for the flowline. Additional protection such as rock placement would be minimal (concrete mattressing and grouting at trench transition areas only).

PROJECT DESCRIPTION

SCHEDULE

Drilling is scheduled between September 2012 and December 2012. The production flowline, umbilical and power cable are planned to be installed between April and November 2013 (although there is a possibility for early installation between August and October 2012). First oil is expected to be in October 2013 and field life is anticipated to be ten years.

CONSTRUCTION

The development will consist of:

One oil production well

One 8” production flowline, one control umbilical and one power cable in separate trenches An overview of the Galia field development is shown in Figure 1 below.

The production well will target the Fulmar reservoir within the Galia Development area and will be drilled in five sections using a combination of water based mud (WBM) and oil based mud (OBM), with each section cement cased. WBM and associated cuttings will either be discharged at the seabed or to sea from the drilling rig after passing over the shale shakers. All OBM and associated cuttings will be skipped and shipped to shore for processing and disposal. EnQuest plans to use the Ocean Princess semi-sub drilling rig, or if unavailable, a rig with similar specifications. The rig uses eight anchors to maintain position in a pattern within 1,500m radius of the drill centre (Figure 5-4).

Concrete mattresses will be used to protect the flowline, control umbilical and power cable from dropped objects and for stability on the approach to the Galia tree and the Alma production manifold. Approximately 25 mattresses will be used per line at each end, with a total of 150 mattresses for the development. After tie-in, the flowline will be hydrotested and leak tested before being dewatered and then commissioned. The flowline will terminate directly in the Alma production manifold.

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure 1: Alma and Galia Field Development Layout

Note: Image is for illustrative purposes only and does not necessarily reflect exact layout of flowlines and associated infrastructure

PRODUCTION

Crude oil and associated gas will be produced back to the FPSO via the Alma production manifold and oil then offloaded onto shuttle tankers for export.

Current estimates are that, based on a 10 year field life, the low case recovery from the Galia field will be 0.880 million tonnes (1.054 million m3), 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).

Alma and Galia produced fluids will be co-mingled at the Alma production manifold. Produced water (PW) from both fields will be passed through a bank of hydrocyclones which will take oil in water (OIW) concentrations from approximately 1000mgl-1 to below 30mgl-1. PW will then be routed through a degasser and settling vessel and into four injection pumps. The injection pumps push the PW down the Alma water injection flowline, where it will be re- injected into one of the Alma water injection (WI) wells. Should any PW be discharged (as a

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

result unavailability of the injection wells at start up, or due to temporary failure, or routine maintenance of the PW re-injection system) then OIW concentrations will be below 30mgl-1.

Sufficient quantities of gas are expected to be produced with the crude to be used for power generation onboard the FPSO. Early in the field life (to 2014) there may be excess gas which will need to be flared. For the high production case, this could be up to 93.5 million m3 of gas over the field life. The base case flaring is about 53% of this figure.

DECOMMISSIONING

Field life is expected to be ten years. Before the end of field life, arrangements for decommissioning will be developed in accordance with the prevailing UK government and international legislation. The development plan is based on the assumption that similar requirements to current legislation will be applicable. These requirements have been considered in the design of the facilities and during project planning. The impacts of decommissioning activities on the environment have not been assessed under the scope of this document as they will be the subject of a separate EIA.

ACCIDENTAL EVENTS

Three types of accidental event were considered by the EIA: hydrocarbon spills and leaks; chemical spills and leaks; and dropped objects. In accordance with the current UK legislation the accidental release of hydrocarbons from the identified potential worst case scenarios was modelled and assessed to characterise the extent of potential impacts. Three worst case scenarios were considered:

Loss of well control e.g. a well blow out resulting in a crude oil spill of 1,992 tonnes (2,385m3) of crude oil per day.

Full loss of containment from the export tanker due to collision with the FPSO resulting in a maximum 87,000 tonnes (100,000m3) of crude oil released instantaneously.

Loss of containment from the FPSO and export tanker due to collision with each other, resulting in 4,897 tonnes (5,830m3) of diesel released instantaneously. Modelling undertaken for the above scenarios indicates that:

Crude oil from the well blow out could beach on the UK coastline within 8 days and 10 hours and on the Danish coastline within 5 days and 17 hours. The spill will have completely dispersed within 417 days. Depending on the prevailing wind condition at the time of the event there is a 1% chance of oil beaching anywhere along the coastlines of the majority of countries bordering the North Sea (Figure 6-1 and 6-2).

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Crude oil from the export tanker could beach on the UK coastline within 9 days. It will have crossed the UK/Norwegian median line within 5 hours, the Norway/Denmark median line within 31 hours and beached on the Danish coastline within 6 days. The spill will have fully dispersed within 417 days.

Diesel from the FPSO/tanker collision will either be evaporated or dispersed within 10 hours of the spill occurring and will not beach on any coastline.

ENVIRONMENTAL IMPACT AND MITIGATION

Mitigation is an integral part of the Galia development. All of the potential interactions between project activities and environmental receptors are subject to either standard recognised best practice mitigation measures or to impact specific, feasible and cost effective mitigation.

The following table summarises the findings of the detailed EIA process undertaken in relation to the Galia development and its potential effects on the physical, biological and human environment.

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact Construction Seabed The Galia development area comprises a Minor The footprint of the Conditions: <2m thickness of very loose to loose silty development will be Disaggregation shelly sands (with a varying degree of minimised. of surface gravel and shells) over firm to very stiff sediments sandy gravelly clay. A number of Change in activities have the potential to affect seabed seabed conditions e.g., anchoring, topography trenching and the deposition of drill cuttings. When retrieved, the anchors are expected to leave a small area of residual disturbance on the seabed. Peak seabed currents (0.42ms-1) will ensure that all cuttings piles will disperse quickly, although there is the possibility that they may persist for a number of years Seabed Site surveys of the Galia field indicate that Minor Daily recording of chemical Conditions: there is a level of sediment contamination use to allow more refined Sediment as a result of the historic use of the area and efficient use. contamination for previous oil and gas developments. It Where possible chemicals is unlikely that further drilling at the site will be recycled, skipped and will increase this contamination as shipped or re-injected and chemicals discharged at the seabed are

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact typically environmentally benign. No OBM not discharged. will be discharged. Selections of chemicals will be made in accordance with the CEFAS ranked list, where chemicals ranked as lower potential hazards are preferentially chosen. Benthic The benthic community is typical of a Minor Communities: sandy biotope with moderate diversity. Only chemicals permitted Potential toxic No rare or protected species were through the relevant effects identified in the baseline survey. All Offshore Chemicals seabed chemical discharges will be risk Regulations chemical permit assessed and will be within permitted (i.e. PON15B or PON15C) levels. and that have been subject to a risk assessment will be discharged. Benthic A total of 8 anchors will be deployed Minor The development footprint Communities: within a 1,500m radius of the rig at the drill will be minimised where Physical site. The total area of seabed impacted operationally possible. damage to by all anchors and chains has been individuals or estimated at 2,600m2. Communities are habitats and expected to recover within two years smothering following cessation of disturbance. (Anchoring) Cuttings discharged at the seabed will have a direct impact on the benthic community. Cuttings discharged through Physical the water column could have an impact No mitigation envisaged damage to on the benthic community as they settle individuals or out on the seabed. Cuttings will be habitats and incorporated in the sediment through smothering bioturbation and general sediment (Drill cuttings) mobility. Significant erosion of cuttings piles starts when the seabed critical velocity reaches 0.35ms-1 (UKOOA 1999). Local seabed currents (0.42ms-1) will ensure that all cuttings piles will disperse quickly, although there is the possibility that they may persist for a number of years. Experience in the CNS region indicates that cuttings piles will persist for 5-10 years.

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact Fish and Mackerel, lemon sole, sprat, haddock and Minor No mitigation envisaged Shellfish: whiting all spawn and/or nurse in the Loss or vicinity of the Galia development. disturbance of Spawning occurs mainly between April spawning and and September, with peaks in May, June nursery and July. Juveniles may be present in the grounds region all year round. effecting stock As the majority of the noise generated by viability offshore oil installations is low frequency (<1kHz), and no piling will be carried out at Galia, any impact is likely to be minimal. Cuttings discharged through the water column could have an impact on pelagic fish species and could also have an impact on benthic species, spawning grounds and shellfish as they settle out on the seabed. Seabed currents (0.42ms-1) will ensure that all cuttings piles will disperse quickly, although there is the possibility that they may persist for a number of years. Commercial The project area is not considered to be a Minor A 500m safety exclusion Fishing: commercially important for fishing. zone will be enforced Impacts on Exclusion from fishing grounds, the around the drilling rig at vessels potential impact of anchoring on fish each location. spawning areas and stocks and the A 500m safety corridor will physical presence of flowlines and be established along the concrete mattresses were the only route of the production impacts deemed to have any residual flowline, umbilical and power impact on fishing gear after mitigation. cable. Shipping and The nearest shipping route is within 2nm Minor The drilling rig and Navigation: of the Galia development. Some shipping construction vessels will be Impact on will be displaced from the immediate appropriately lit and sound vessel vicinity of the development; however there warnings will be broadcast movement is ample sea room to do so. The 500m in poor visibility. safety exclusion zone around the drilling Users of the sea will be rig is intended to prevent potential notified of the presence and collisions with any vessels that may be in intended movements of the area. This will be enforced by a guard construction vessels via the vessel. Kingfisher fortnightly bulletins, Notices to Mariners and VHF radio broadcast.

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact Archaeology: It is unlikely that any remains of Minor The British Marine Physical archaeological significance exist within Aggregate Producers damage to the Galia area. It is therefore likely that Association (BMAPA) undiscovered any damage would be of minor protocol for reporting finds of archaeology significance, while the value of the archaeological significance discovery may be of moderate/major will be followed (positive) significance. Production Commercial The project area is not considered to be a Minor A 500m safety exclusion Fishing: commercially important for fishing. The zone will be enforced Exclusion from continued presence of development and around the Galia well. fishing grounds the exclusion zones around the drill Users of the sea will be Potential centre will typically preclude fishing in this notified of the presence of collision risk area due to the small development size. the new safety exclusion zone via the Kingfisher fortnightly bulletins, Notices to Mariners and VHF radio broadcast. All vessels will comply with international navigation regulations and codes. Accidental Events Water In the unlikely event of a spill greater than Minor Accidental spills will be kept Resource: 10 tonnes, water quality is likely to to a minimum through Deterioration in deteriorate in the immediate vicinity of the training, good housekeeping water quality spill as potential spillages of hydrocarbons and through are dispersed through the water column. storage/handling procedures However these will be naturally e.g., sumps, drains and biodegraded by microbes within one to bunding should catch two months (NOAA 2006). The accidental spills. concentration and likelihood of natural Management controls will be biodegradation will obviously be in place to eliminate dependent on the scale of the incident. bunkering spills e.g. only However, generally the deterioration in bunkering during day light water quality will be short –term. and in good weather. Seabed The majority of spills are likely to be at the Minor A location specific OPEP will Conditions: sea surface or in the water column. The be in place for the drilling rig Sediment likelihood of a spill between 1 and 10 and a further OPEP will be contamination tonnes occurring during construction is applied for to cover 0.5% for the Galia development. The production operation. The probability of an incident involving the OPEPs will detail all subsea system is approximately 3% over emergency procedures that field life (Section 6.2.2). A spill of crude oil will be in place to minimise from the production flowline could

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact contaminate sediments and persist for any spill. some time however the extent will be EnQuest has access to Tier localised. 1, 2 and 3 oil spill response Any components that settle to the seabed capabilities through Oil Spill will be naturally biodegraded by microbes Response (OSR). within one to two months. Elevated EnQuest is a member of concentrations of hydrocarbons may be OSPRAG which will provide noticeable in sediments close to the support in a well blow out discharge point after a large spill. Given event. the previous use of the area for oil and Control measures will be in gas development, levels of hydrocarbon place to ensure rapid contamination are not expected to rise response to loss of flowline over existing historical levels. containment. These will be Crude oil that beaches has the potential outlined in the Galia OPEP. to contaminate beach sediments. However a spill of this magnitude is extremely rare. Plankton: Marine ecology is typical for the CNS with Minor Potential toxic no rare or protected benthic species effect identified in the baseline survey. Nine cetacean species may occur in the area, Benthic Minor all of which are protected under the EC Communities: Habitats Directive. The region is also Potential toxic important for seabirds. effect Biological receptors are vulnerable to the Fish and Minor accidental release of hydrocarbons and/or Shellfish: chemicals. A small spill of diesel of crude Potential toxic will rapidly disperse and dilute in the effect energetic marine environment but a larger Seabirds: spill as a result of a loss of well control Moderate Smothering has the potential to have wider reaching Marine impacts. Major accidental events are Minor Mammals and extremely unlikely to occur. Modelling Protected suggests that under typical meteorological Species: conditions, there is the potential for an oil Smothering slick as a result of the loss of well control to beach along the coastlines of the majority of countries bordering the North Sea (total probability of beaching anywhere is 1%). Numerous protected areas could potentially be impacted as shown in Figure 8-3. Commercial A major crude oil spill would have the Minor Fishing: potential to cause damage to the fishing Damage to industry by long-term effects on fish

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Receptor & Baseline & Impact Assessment Significance Control and Mitigation Type of Impact of Residual Impact vessels and stocks and damage to market confidence decrease in and could potentially exclude shipping catch from a number of key shipping lanes. Shipping and However, the likelihood of such an event Minor Navigation: occurring is extremely rare. Impact on vessel movement Other Marine Minor Users: Damage to vessels

CUMULATIVE AND INDIRECT IMPACTS

The main concerns regarding the potential for cumulative and indirect impacts from the proposed development relate to impacts from activities at Galia interacting with:

Other activities within the project

Other oil and gas developments (past and future)

Other marine users, such as windfarms, commercial fishing, marine aggregate extraction areas etc

Climate change The EIA drew the following conclusions:

The project will not have any significant cumulative or indirect effects with any other oil and gas developments

The project will not have any significant cumulative or indirect effects with any other seabed users

The project will not disproportionably exacerbate the changes predicted to occur as a consequence of climate change. Residual impacts on the environment will be short-term, predominantly affecting marine ecology. The EIA concludes that, following construction, biological communities are anticipated to recover to pre-impact levels/structures or similar within five years (see Section 8.2.5). Given the relatively short timescale of the construction impacts, it is considered unlikely that any cumulative impacts from the project and climate change will have significant impacts on marine ecology.

ENVIRONMENTAL MANAGEMENT SYSTEMS

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

The EnQuest corporate policies and health, safety and environmental management system (HS&EMS) provide a fit for purpose framework to implement the mitigation measures proposed in this ES. The HS&EMS also provides adequate control and bridging arrangements for EnQuest to ensure that the contractors implement these mitigation measures. During the construction and production operations, a set of permits and consents will be obtained from the regulatory bodies. Permit conditions under these will also be fed into the HS&EMS to ensure compliance. HS&EMS performance will be regularly benchmarked against recommendations from independent verifications, through internal and independent audits and reviews.

The HS&EMS is designed to match the requirements of ISO-14001:2004 and is based on the requirements of the Health and Safety OHSAS 18001 standard. The management systems are designed to cover HSEQ aspects which EnQuest can control and directly manage and those it does not control or directly manage, but can be expected to influence. EnQuest requires all contractors, their subcontractors and suppliers to have and be responsible for their own HS&EMS. However, contractors HS&EMS must be compatible with EnQuest’s HS&EMS.

An HS&E plan will be developed to cover both the Alma and Galia developments which will define how EnQuest will manage HS&E risks and activities and it is expected that the mitigation measures identified in the EIA process and reported in this ES will be adopted and bridged into EnQuest’s HSEQ Management System.

CONCLUSIONS

The Environmental Impact Assessment has established that:

Protected Sites & Species: No habitats of conservation significance under the UK’s Offshore Marine Conservation (Natural Habitats, &c.) (Amendment) Regulations 2010 were observed during seabed surveys. One individual of Arctica islandica (listed by OSPAR (2008) as a species under threat and/or in decline in the North Sea) was identified at sampling station ENV9. At all other stations no habitats or species of conservation significance under the UK’s Offshore Marine Conservation (Natural Habitats, &c) (Amendment) Regulations 2010, which implement the requirements of the EC Habitats Directive, were observed (GEL 2011). There are no protected sites within 40km of the Galia development. The nearest protected site is the Dogger Bank candidate Special Area of Conservation (cSAC) which is approximately 78km south- east from the drill centre. Due to the distance of the protected site from the development area, it is unlikely that there will be any impacts during normal activities.

2 Benthic Environment: The total seabed footprint of the development is 0.33km . Due to fishing activities and previous oil and gas industry activities, the benthos in the project area is typical of a moderately disturbed habitat and consequently species that inhabit the area tend to recover quickly after disturbance. The development area is sufficiently homogenous that any localised losses are unlikely to affect the integrity of

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

the community as a whole. The placement of protective structures such as concrete mattresses will create new habitat for those species that require hard substrate for anchoring. This could lead to settlement of new species and the potential for a localised change in marine ecology. Current speeds are sufficient to erode cuttings piles and these are unlikely to persist for a long period of time. Seabed activities that cause physical disturbance have been classed as having a moderate to minor residual impact.

Marine mammals are likely to be the only protected species of relevance in the Galia development area. No piling will take place at Galia and therefore there is therefore a negligible risk of an offence under the Conservation (Natural Habitats &c) Regulations 1994 (as amended) and the Offshore Marine Conservation (Natural Habitats &c) Regulation 2007 (as amended in 2010).

Water/Sediment Quality: No activities were identified during construction or production that would have the potential to have a significant residual impact on water or sediment quality.

Climate Change: Although identified as having a moderate impact, the emissions from Galia represent a small proportion of the total UKCS E&P contribution. Therefore it is not expected that there will be any residual impact on climate change (Section 5.5.1).

Commercial Fishing: With consideration of other development activities in the CNS, the project will have a minor contribution to seabed smothering from cuttings piles, infrastructure installation and anchoring. However, this is anticipated to be limited to within the immediate vicinity of the well. The safety exclusion zone around the wellhead is likely to have a minor impact on commercial fishing in the area. Overall it is concluded cumulative impacts and the in-combination impacts with the fishing industry and other marine users are likely to be of negligible significance.

Oil/Chemical Spill Pollution: During construction a loss of well control would result in a release of 29,880 tonnes (35,775m3) of crude oil over 15 days. Modelling shows that depending on the prevailing wind conditions there is a 1% chance of beaching occurring on a coastline of a North Sea bordering country. Modelling also indicates that, without an intervention response, depending on the prevailing wind conditions, the spill could reach the UK coastline within 8 days and 10 hours and the Danish coastline within 5 days and 17 hours. There are numerous protected areas along the coastlines of North Sea bordering countries that could be affected by a spill (Figure 8-3). During production, a worst case scenario loss of containment of 87,000 tonnes (100,000m3) of crude oil from the export tanker was been modelled. Results are extremely similar to those seen for the loss of well control. EnQuest will have an Oil Spill Contingency Plan (OPEP) in place to manage spill response.

EMS: EnQuest corporate policies and environmental management system will provide a fit for purpose framework to implement the mitigation measures proposed in this ES. The EMS will also provide adequate control and bridging arrangements for EnQuest to ensure that the contractors implement these mitigation measures. During the construction and production operations, a set of permits and consents will be obtained from the regulatory bodies. Permit conditions under these will also be fed into the EMS to ensure compliance. EMS performance will be regularly benchmarked against recommendations from independent verifications, through internal and independent audits and reviews. With mitigation measures in place, the Galia Field development will have a minor impact on the environment.

REPORT REF: GALIA ES D/4127/2011 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

CONTENTS

1 INTRODUCTION ...... 1

1.1 THE DEVELOPER ...... 1 1.2 PROJECT OVERVIEW ...... 1 1.3 FORMAT OF THE ES ...... 6 1.4 ES AVAILABILITY ...... 7

2 INSTITUTIONAL POLICY AND REGULATORY FRAMEWORK ...... 8

2.1 INTERNATIONAL CONVENTIONS, EC LAW, UK LAW AND POLICIES ...... 8 2.2 SEA AND EIA GUIDELINES ...... 9 2.3 UK INSTITUTIONAL FRAMEWORK ...... 10 2.4 ENQUEST CORPORATE POLICY ...... 11

3 PROJECT JUSTIFICATION AND ALTERNATIVES ...... 13

3.1 PROJECT JUSTIFICATION ...... 13 3.2 PROJECT ALTERNATIVES ...... 15

4 IMPACT ASSESSMENT METHODOLOGY ...... 20

4.1 ENVIRONMENTAL AND HUMAN IMPACT ASSESSMENT PROCESS ...... 20 4.2 CUMULATIVE AND INDIRECT IMPACTS ...... 30 4.3 EIA STAKEHOLDER CONSULTATION ...... 31

5 PROJECT DESCRIPTION AND FOOTPRINT ...... 32

5.1 SCHEDULE ...... 33 5.2 CONSTRUCTION ...... 34 5.3 PRODUCTION ...... 49 5.4 DECOMMISSIONING ...... 54 5.5 PROJECT ACTIVITY SUMMARY ...... 54

6 ACCIDENTAL EVENTS ...... 59

6.1 TYPES OF ACCIDENTAL EVENT ...... 59 6.2 PROBABILITY OF ACCIDENTAL EVENTS OCCURRING ...... 62 6.3 MANAGEMENT AND MITIGATION FOR HYDROCARBON SPILLS ...... 64 6.4 OIL SPILL MODELLING ...... 66

7 IMPACTS ON PHYSICAL ENVIRONMENT ...... 69

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

7.1 AIR ...... 69 7.2 CLIMATE CHANGE ...... 72 7.3 WATER RESOURCES ...... 74 7.4 SEABED CONDITIONS ...... 81

8 IMPACTS ON BIOLOGICAL ENVIRONMENT ...... 89

8.1 PLANKTON ...... 89 8.2 BENTHIC COMMUNITIES ...... 91 8.3 FISH AND SHELLFISH ...... 96 8.4 SEABIRDS ...... 100 8.5 MARINE MAMMALS ...... 104 8.6 PROTECTED SITES AND SPECIES ...... 110

9 IMPACTS ON HUMAN ENVIRONMENT ...... 115

9.1 COMMERCIAL FISHERIES ...... 115 9.2 SHIPPING AND NAVIGATION ...... 121 9.3 OTHER MARINE USERS ...... 125 9.4 ARCHAEOLOGY ...... 129

10 CUMULATIVE AND INDIRECT IMPACTS ...... 132

10.1 OTHER OIL AND GAS DEVELOPMENTS ...... 132 10.2 OTHER SEABED USERS ...... 135 10.3 CONCLUSION ...... 136

11 ENVIRONMENTAL MANAGEMENT ...... 137

11.1 MANAGEMENT SYSTEM ...... 137 11.2 PROJECT SPECIFIC ENVIRONMENTAL MANAGEMENT ...... 137 11.3 MANAGEMENT OF CONTROL & MITIGATION MEASURES ...... 140 11.4 OIL SPILL RESPONSE ...... 142

12 CONCLUSIONS ...... 144

12.1 THE PROJECT ...... 144 12.2 EXISTING ENVIRONMENT ...... 144 12.3 POTENTIAL IMPACTS ...... 145 12.4 DECOMMISSIONING ...... 146 12.5 ENVIRONMENTAL MANAGEMENT ...... 147

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

13 REFERENCES ...... 148

APPENDIX A ENVIRONMENTAL IMPACT ASSESSMENT ...... A-1

APPENDIX B OIL SPILL MODELLING ...... B-1

APPENDIX C SUMMARY OF CHEMICALS ...... C-1

APPENDIX D INSTITUTIONAL POLICY AND REGULATORY FRAMEWORK .. D-1

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

TABLES

TABLE 1-1: PROJECT CO-ORDINATES ...... 3 TABLE 1-2: STRUCTURE OF THIS ES ...... 6 TABLE 2-1: SUMMARY OF INTERNATIONAL CONVENTIONS, EC LAW AND UK LAW AND POLICY RELEVANT TO THE PROJECT ...... 8 TABLE 3-1: CUMULATIVE (BY YEAR) PRODUCTION PROFILES ...... 14 TABLE 3-2: ADVANTAGES AND DISADVANTAGES OF DIFFERENT DEVELOPMENT SCENARIOS ...... 17 TABLE 4-1: PROJECT ACTIVITIES ...... 24 TABLE 4-2: EXTRACT FROM THE GALIA ISSUES INTERACTION MATRIX ...... 25 TABLE 4-3: EXAMPLE DEVELOPMENT ACTIVITY, ASPECT AND IMPACT IDENTIFICATION ...... 25 TABLE 4-4: ASSESSMENT PROCESS FOR IDENTIFICATION OF POTENTIAL IMPACTS ...... 26 TABLE 4-5: SEVERITY DEFINITIONS ...... 27 TABLE 4-6: ENVIRONMENTAL AND HUMAN IMPACT SIGNIFICANCE ASSESSMENT MATRIX ...... 28 TABLE 5-1: PROJECT SCHEDULE ...... 33 TABLE 5-2: DRILLING EXHAUST GAS EMISSIONS ...... 37 TABLE 5-3: SUMMARY OF DRILLING NOISE SOURCES AND ACTIVITIES ...... 38 3 TABLE 5-4: TOTAL WASTE WATER DISCHARGE (M ) DURING DRILLING ...... 39 TABLE 5-5: SUMMARY OF UNDERWATER NOISE PRODUCED DURING DRILLING ACTIVITIES ...... 39 TABLE 5-6: WEIGHT AND DISCHARGE FATE OF DRILL CUTTINGS (TONNES) ...... 42 TABLE 5-7: SACRIFICIAL ANODE COMPOSITION ...... 47 TABLE 5-8: FLOWLINE INSTALLATION EXHAUST GAS EMISSIONS ...... 48 TABLE 5-9: TOTAL WASTE WATER DISCHARGE DURING INSTALLATION AND TIE-IN ...... 48 TABLE 5-10: SUMMARY OF INSTALLATION FOOTPRINT ON THE SEABED ...... 49 TABLE 5-11: PRODUCTION ESTIMATES FOR GALIA AND ALMA...... 50 TABLE 5-12: FLARING GAS EMISSIONS DURING PRODUCTION ...... 53 TABLE 5-13: SUMMARY OF PROJECT ACTIVITIES AND ASPECTS ...... 55 TABLE 5-14: SUMMARY OF EMISSIONS TO AIR FROM CONSTRUCTION AND PRODUCTION ACTIVITIES ...... 56 TABLE 5-15: TOTAL WASTE WATER DISCHARGE DURING CONSTRUCTION ...... 57 TABLE 5-16: SUMMARY OF SEABED FOOTPRINT - FIELD DEVELOPMENT ...... 58 TABLE 6-1: INDUSTRY RISER AND PIPELINES FAILURE FREQUENCIES ...... 64 TABLE 7-1: AIR QUALITY – POTENTIAL IMPACT IDENTIFICATION ...... 72 TABLE 7-2: RECOMMENDED CONTINGENCY ALLOWANCES FOR NET SEA LEVEL RISE ...... 73 TABLE 7-3: CLIMATE CHANGE – POTENTIAL IMPACT IDENTIFICATION ...... 74

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

TABLE 7-4: PHYSICAL CHARACTERISTICS OF THE SEA WATER IN THE GALIA FIELD ...... 75 TABLE 7-5: SUMMARY OF NORTH SEA SURFACE WATERS CONTAMINANT LEVELS ...... 76 TABLE 7-6: SUMMARY OF TIDAL CURRENT SPEEDS AT THE ALMA FIELD ...... 77 TABLE 7-7: WAVE CHARACTERISTICS AT ALMA ...... 78 TABLE 7-8: WATER RESOURCES – POTENTIAL IMPACT IDENTIFICATION ...... 78 TABLE 7-9: PW DISCHARGE DURING PRODUCTION ...... 81 -1 TABLE 7-10: HEAVY METALS IN SEDIMENT (µGG ) ...... 85 TABLE 7-11: SEABED CONDITIONS – POTENTIAL IMPACT IDENTIFICATION ...... 87 TABLE 8-1: PLANKTON – POTENTIAL IMPACT IDENTIFICATION ...... 90 TABLE 8-2: CONTRIBUTIONS OF THE GROSS TAXONOMIC GROUPS ...... 92 TABLE 8-3: SPECIES RANKING ...... 93 TABLE 8-4: BENTHIC COMMUNITIES – POTENTIAL IMPACT IDENTIFICATION ...... 95 TABLE 8-5: COMMONLY CAUGHT SPECIES IN ICES RECTANGLE 41F2 ...... 97 TABLE 8-6: KEY SENSITIVE PERIODS FOR FISH SPAWNING AND NURSERY ...... 97 TABLE 8-7: FISH AND SHELLFISH – POTENTIAL IMPACT IDENTIFICATION ...... 98 TABLE 8-8: SEABIRD VULNERABILITY IN THE VICINITY OF BLOCK 30/24 ...... 102 TABLE 8-9: SEABIRDS – POTENTIAL IMPACT IDENTIFICATION ...... 103 TABLE 8-10: CETACEAN OBSERVATIONS IN THE AREA OF INTEREST ...... 105 TABLE 8-11: CETACEAN POPULATION ESTIMATES AND CONSERVATION STATUS ...... 106 TABLE 8-12: MARINE MAMMALS – POTENTIAL IMPACT IDENTIFICATION ...... 108 TABLE 8-13: PROTECTED SITES AND SPECIES – POTENTIAL IMPACT IDENTIFICATION ...... 112 TABLE 9-1: VALUE (£) OF LANDING FOR THE GALIA DEVELOPMENT AREA AND SURROUNDING REGION (2004 – 2010) ...... 116 TABLE 9-2: COMMERCIAL FISHING – POTENTIAL IMPACT IDENTIFICATION ...... 119 TABLE 9-3: SHIP ROUTES ...... 122 TABLE 9-4: SHIPPING AND NAVIGATION – POTENTIAL IMPACT IDENTIFICATION ...... 123 TABLE 9-5: WELLS WITHIN 40KM OF THE DEVELOPMENT ...... 125 TABLE 9-6: OTHER MARINE USERS’ POTENTIAL IMPACT IDENTIFICATION ...... 126 TABLE 9-7: ARCHAEOLOGY POTENTIAL IMPACT IDENTIFICATION ...... 131 TABLE 11-1: ENQUEST ENVIRONMENTAL TARGETS ...... 138 TABLE 11-2: SUMMARY OF CONTROL & MITIGATION MEASURES ...... 140 TABLE 11-3: SUMMARY OF COMMITMENTS ...... 141

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

FIGURES

FIGURE 1-1: PROJECT LOCATION ...... 2 FIGURE 2-1: ENQUEST HSEQ POLICY ...... 12 FIGURE 4-1: OVERVIEW OF EIA METHODOLOGY ...... 20 FIGURE 4-2: GALIA DEVELOPMENT SURVEY EXTENTS ...... 23 FIGURE 5-1: GALIA FIELD DEVELOPMENT ...... 33 FIGURE 5-2: OCEAN PRINCESS SEMI-SUBMERSIBLE DRILLING RIG ...... 34 FIGURE 5-3: FIELD LAYOUT SHOWING ANCHOR PATTERNS FOR GALIA IN RELATION TO ALMA DEVELOPMENT ...... 41 FIGURE 5-4: AREA OF SEABED COVERED BY CUTTINGS PILE ...... 43 FIGURE 5-5: TYPICAL MULTI-PASS PLOUGH ...... 44 FIGURE 5-6: TYPICAL TRENCH CREATED BY DISPLACEMENT PLOUGH ...... 45 FIGURE 5-7: INDICATIVE TRENCH PROFILE CREATED BY MMP PLOUGH ...... 45 FIGURE 5-8: ENQUEST PRODUCER FPSO ...... 50 3 FIGURE 6-1: STOCHASTIC MODEL RUN – BLOW OUT OF 35,775M OF HYDROCARBONS OVER 15 DAYS ...... 67 FIGURE 6-2: POSSIBLE BEACHING LOCATIONS ...... 68 FIGURE 7-1: ANNUAL WIND ROSE FOR THE GALIA AREA ...... 71 FIGURE 7-2: GENERAL CURRENT CIRCULATION IN THE NORTH SEA ...... 77 FIGURE 7-3: BATHYMETRY AT GALIA DRILL CENTRE ...... 83 FIGURE 7-4: EXAMPLE OF SEABED SEDIMENTS FROM SURVEY ...... 84 FIGURE 8-1: SEABED PHOTOGRAPHS OF THE GALIA DEVELOPMENT AREA ...... 94 FIGURE 8-2: ENVIRONMENTAL OVERVIEW ...... 101 FIGURE 8-3: OIL SPILL BEACHING LOCATIONS IN RELATION TO PROTECTED SITES ...... 114 FIGURE 9-1: SEASONAL VARIATION IN FISHING ACTIVITY (2004-2010) ...... 117 FIGURE 9-2: AVERAGE ANNUAL CATCH AND VALUE FOR THE GALIA DEVELOPMENT AREA ...... 118 FIGURE 9-3: SHIPPING ROUTE POSITIONS WITHIN 10NM OF ALMA AND GALIA LOCATIONS ...... 122 FIGURE 9-4: OTHER MARINE USERS ...... 128

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

ACRONYMNS AND UNITS

< Less than > More than A ACOPS Advisory Committee on Protection of the Sea ALSF Aggregates Levy Sustainability Fund API American Petroleum Institute B B.P Before Present BAT Best Available Technique bbls Barrels BGS British Geological Society BOP Blow-Out Preventer bopd Barrels of Oil Per Day BS&W Bottom Sediment and Water BSI British Standards Institute bwpd Barrels of Water Per Day C CBD Convention on Biological Diversity CEFAS Centre for Environment, Fisheries and Aquaculture Science

CH4 Methane CMT Crisis Management Team CNS Central North Sea CO Carbon Monoxide

CO2 Carbon Dioxide CPR Continuous Plankton Recorder D dB Decibel DECC Department of Energy and Climate Change Defra Department for Environment, Food and Rural Affairs DMRB Design Manual for Roads and Bridges DP Dynamic Positioning DSV Diving Support Vessel DTI Department of Trade and Industry E EC European Commission EEMS Environmental Emissions Monitoring Scheme EIA Environmental Impact Assessment EMS Environmental Management System EPS European Protected Species ERC Emergency Response Centre ES Environmental Statement ESP Electrical Submersible Pump EU ETS European Union Emissions Trading Scheme

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

F FAO Food and Agriculture Organisation FDP Field Development Plan FPSO Floating, Production, Storage and Offloading FRS Fisheries Research Service G GESAMP The Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection GGL Gardline Geosurvey Limited GHG Greenhouse Gases GIS Geographical Information Service H HQ Hazard Quotient HR Conservation (Natural Habitats &c.) Regulations 1994 (as amended) HSE Health and Safety Executive HSEQ Health, Safety, Environment and Quality Hz Hertz I IBA Important Bird Areas ICES International Council for the Exploration of the Seas IMT Incident Management Team IPPC Integrated Pollution Prevention and Control Directive ISO International Organization of Standardization J JNCC Joint Nature Conservation Committee K KISCA Kingfisher Cables km Kilometre km2 Kilometres squared kPa Kilo Pascal kW Kilo Watt L LAQM Local Air Quality Management (LAQM) Support. Defra, UK Local Air Quality Management LAT Lowest Astronomical Tide M µgl-1 Microgram per Litre µgm-3 Microgram per cubic metre µPa Micro Pascal m metre m2 metre squared m3 cubic metre MBES Multi-Beam Echo Sounder MCA Maritime and Coastguard Agency MCAA Marine and Coastal Access Act MCZ Marine Conservation Zone MEG Monoethylene Glycol mgl-1 milligram per litre mmbbls Million barrels MMO Marine Mammal Observer MMO Marine Management Organisation

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

MMscf/d Million standard cubic foot per day MODU Mobile Offshore Drilling Unit ms-1 Metres per Second MW Mega Watt MW(th) Mega Watt (Thermal) MWh Mega Watt Hour

N N2O Nitrous Oxide NER New Entrants Reserve NM Nautical Miles NNE North-North East NNS Northern North Sea

NO2 Nitrogen Dioxide NOEC No Observed Effect Concentration

NOx Nitric Oxides O OBM Oil Based Mud OCNS Offshore Chemical Notification Scheme OCR Offshore Chemical Regulators OESEA Offshore Energy Strategic Environmental Assessment OGED Oil and Gas Exploration and Development OGUK Oil and Gas UK OIW Oil in Water OMR Offshore Marine Conservation (Natural Habitats &c) Regulations 2007 (as amended in 2010) OPEP Oil Pollution Emergency Plan OPPC Oil Pollution Prevention and Control OSPAR Convention for the Protection of the Marine Environment of the North East Atlantic (Oslo Paris Convention) OSRL Oil Spill Response Limited P PAH Polycyclic Aromatic Hydrocarbons PAIH Potential Annex I Habitat PEXA Practice and Exercise Areas PIG Pipeline Inspection Gauge PLANC Permits Licenses Approvals Notifications and Consents PLONOR Posing Little or No Risk PLV Pipeline Laying Vessels PM 10 Particles Measuring 10µm or less PM 2.5 Particles Measuring 2.5µm or less PON Petroleum Operations Notice ppb Parts per billion ppm Parts per million PSA Particle size analysis

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

psia Pounds per square inch atmospheric PW Produced Water PWA Pipelines Works Authorisation PWRI Produced Water Reinjection Q QMS Quality Management System R REACH Registration, Evaluation, Authorisation and restriction of Chemicals ROV Remotely Operated Vehicle RYA Royal Yachting Association S SAC Special Area of Conservation SCANS Small Cetaceans in the European Atlantic and North Sea scfd-1 Standard cubic foot per day SCI Sites of Community Importance SEA Strategic Environmental Assessment SFF Scottish Fishermen's Federation SMRU Sea Mammal Research Unit SNS Southern North Sea

SO2 Sulphur Dioxide SoS Secretary of State

SOx Oxides of Sulphur SPA Special Protection Area SPL Sound Pressure Levels SSE Scottish and Southern Energy SSS Sidescan Sonar SSW South-South West SUB Substitution T THC Total Hydrocarbons U UK United Kingdom UK BAP UK Biodiversity Action Plan UKCIP UK Climate Impact Programme UKCP United Kingdom Climate Predictions UKCS United Kingdom Continental Shelf UKMMAS UK Marine Monitoring and Assessment Strategy UKOOA United Kingdom Offshore Operators Association (now Oil and Gas UK) UNFCCC United Nations Framework Convention on Climate Change V VHF Very High Frequency VOC Volatile Organic Compounds W WBM Water Based Mud WLCDF Well Life-Cycle Decision Framework

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 02/05/2012

GLOSSARY

A Air Gun Source of seismic energy used in acquisition of marine seismic data. This gun releases highly compressed air into water. Analogue Survey e.g., bathymetry, sonar imagery and shallow profiling. Technique of representing a sensor's input as amplitude modulated electrical signal (e.g., analogue profiles are output on sweep recorders as opposed to digital). Anode Positive electrode. Appraisal Well Phase of petroleum operations that immediately follows successful exploratory drilling. Appraisal wells might be drilled to determine the size of the oil or gas field and how to develop it most efficiently. Aspect Element of an organisations activities, products or services that can interact with (environmental) the environment. B Backfill The replacement of excavated sediment into a trench. Bathymetry The measurement of the depth of the ocean floor from the water surface; the oceanic equivalent of topography. Beaufort Force Empirical measure (scale of 0 to 12) for describing wind velocity based mainly on observed sea conditions established by Admiral Francis Beaufort (1774 to 1857). Benthic Pertaining to the environment and conditions of organisms living at the bottom of the sea. Biogenic Chemicals or material produced by living organisms or biological processes. Blow-out Uncontrolled flow of reservoir fluids into the wellbore, and sometimes catastrophically to the surface. A blow-out may consist of salt water, oil, gas or a mixture of these. Blow-out Preventer A large valve at the top of a well that may be closed if the drilling crew loses (BOP) control of the pressure within the well. C Catch Per Unit Measurement of the mass of fish caught for a given amount of energy and Effort (CPUE) resources expended by a fishing fleet. Conductor Casing string that is usually put in to the wellbore at the surface to stop the sides of the well falling in. Cone Method of providing data for use in characterising subsurface marine sediments Penetrometer Test consisting of a steel cone that is hydraulically pushed into the ground. Sensors on (CPT) the tip of the cone collect data to classify sediment type by measuring cone-tip pressure and friction. Cuttings Small pieces of rock that break away due to the action of the bit teeth. Cuttings are screened out of the liquid mud system at the shale shakers and are monitored for composition, size, shape, colour, texture, hydrocarbon content and other properties. D Demersal Organisms dwelling at or near the bottom of the sea. Development The phase of petroleum operations that occurs after exploration has proven successful, and before full-scale production. The newly discovered oil or gas field is assessed during an appraisal phase, a plan to fully and efficiently exploit it is

created, and additional wells are usually drilled.

Downhole In a well bore. E Echolocation Used by animals to orientate, navigate, and find food it is the detection of the position, distance and size of an object by means of reflected sound. Echosounding The action or process of sounding or ascertaining the depth of water or of an object below a ship by measuring the time taken for a transmitted sound-signal to return as an echo. Effort Measure of input extended by people to catch fish (expressed in days fished). Environmental The systematic appraisal of the likely effects of a proposed project, activity, or Impact policy on the environment, both positive and negative. Assessment (EIA) Environmental A means of submitting to the regulatory authority, statutory consultees, non- Statement (ES) government organisations and the wider public, the findings of an EIA. Epifauna Organisms living on the seabed surface. Epilithic Organisms growing attached to an inorganic substratum, such as rocks, stones, etc. F Flaring The burning of unwanted gas through a pipe. Flaring is a means of disposal used when there is no way to transport the gas to market and the operator cannot use the gas for another purpose. G Geohazard Any geological or hydrological process that poses a threat to people and/or their property. Geophysical The study of the earth by quantitative physical methods, especially by seismic reflection and refraction, gravity, magnetic, electrical, electromagnetic, and radioactivity methods. Geotechnical The study of soil and rock below the ground to determine its properties. Grey Water Non-industrial wastewater generated from domestic processes such as washing dishes, laundry and bathing. H Hydrotest The process of pumping water through a pipeline at a higher pressure level than is normally used when transporting petroleum to confirm the continued safe operation of the pipeline, ensuring that it's free of any defects. I ICES rectangles Statistical divisions of the sea. Impact Any change to the environment, whether adverse or beneficial, wholly or partially (environmental) resulting from an organisation's activities, products or services. Infauna Organisms that live within the sediment. K Kingfisher Bulletins Fortnightly bulletin providing free safety information to all sea users. Kilometre Point A general term for the distance along a route from a fixed reference point. (KP) L Lowest The lowest level that can be expected to occur under average meteorological Astronomical Tide conditions and under any combination of astronomical conditions. (LAT)

M Macrofauna Benthic animals larger than 1 mm in size and include the large polychaete worms, corals, shellfish, and starfish. Magnetometer An instrument for measuring the strength of a magnetic field. MARPOL International Convention for the Prevention of Pollution from Ships (1973/1978). Convention Median Line Offshore international boundary. Mobile Offshore A generic term for several classes of self-contained floatable or floating drilling Drilling Unit machines such as jack-ups, and semi-submersibles. (MoDU) Multivariate Describes a collection of procedures which involve observation and analysis of two or more statistical variables at a time. N North Atlantic A climatic phenomenon in the North Atlantic Ocean of fluctuations in the Oscillation difference of sea-level pressure between the Icelandic Low and the Azores high. Notices to Mariners Information issued from a number of different sources, such as the UK Hydrographic Office, Trinity House or Local Harbour Authorities and may contain a variety of information such as chart updates, changes in buoyage, prior warning of activities such as dredging, exclusion zones, etc. O Oil Producer A well producing oil. OSPAR Instrument guiding international cooperation on the protection of the marine environment of the North-East Atlantic. P Pelagic Relating to or occurring or living in or frequenting the open ocean. Petrogenic A contaminant produced from unburned petroleum products. Phytoplankton Microscopic floating plants that exist within the water column.

Phytoplankton High concentration of phytoplankton in an area, caused by increased Bloom reproduction. Pinger Seismic source. Platform An offshore structure that is permanently fixed to the seabed used to house workers and machinery needed to drill and then produce oil and natural gas in the ocean. Plugged and To prepare a well to be closed permanently with cement plugs and salvage all Abandoned recoverable equipment, usually after either logs determine there is insufficient hydrocarbon potential to complete the well, or after production operations have drained the reservoir. Potential Annex I Habitat (as defined in Annex I of the EC Habitats Directive) identified in offshore Habitat (PAIH) areas to be put forward to the government for protection as part of the Natura 2000 in UK offshore waters programme. Produced Water Formation water (naturally occurring layer of water in oil and gas reservoirs) and (PW) injected water that is produced along with hydrocarbons. At the surface, the water is separated from the hydrocarbons, treated to remove as much of the hydrocarbons as possible and discharged into the sea or injected back into wells.

R Ramsar Site Wetland of international importance designated under the Ramsar Convention (1971). Receptor Element of the environment that an environmental aspect can interact with or (environmental) impact. Re-injection Method of enhanced oil recovery to compensate for the natural decline of an oil (produced water) field production by increasing the pressure in the reservoir. Produced water is injected to maintain reservoir pressure and hydraulically drive oil toward a producing well. Reservoir Subsurface body of rock having sufficient porosity and permeability to store and transmit fluids Rig A drilling unit that is not permanently fixed to the seabed, e.g., a drillship, a semi- submersible or a jack-up unit. Also means the derrick and its associated machinery. Riser The pipe which connects a rig or platform to a subsea wellhead or subsea pipeline during drilling or production operations to take mud returns to the surface; or the pipe which connects a pipeline to a platform. S Seismic Pertaining to waves of elastic energy, such as that transmitted by P-waves and S- waves, in the frequency range of approximately 1 to 100 Hz, used to interpret the composition, fluid content, extent and geometry of rocks in the subsurface. Semi-Diurnal Occurring once every 12 hours. Semi-Submersible Floating vessel that can be used for drilling supported primarily on large pontoon- Rig like structures submerged below the sea surface usually anchored with six to twelve anchors. Shellfish An aquatic animal, such as a mollusc or crustacean, which has a shell or shell-like exoskeleton. Side-Scan Sonar Sonar device used for mapping the seabed. (SSS) Spawning Reproductive activity of fish; the act of releasing eggs into the water by female fish for fertilisation by male fish. Species A group of related organisms having common characteristics and capable of interbreeding. Stochastic Model A model showing the probability of where an oil spill may impact for defined time periods as a result of wind speed and directions. Subsea Situated or occurring underwater. Subsea Control Subsea system that provides electro/hydraulic control of subsea and downhole System hydraulically operated valves. It also provides a data link to the platform control system conveying subsea/downhole operating parameters and performance. Subsea Control Connects remotely positioned subsea satellite production and/or injection trees to Umbilical subsea template controls or to surface controls on a platform. An umbilical can include up to eighteen separate control hoses within a casing e.g., hydraulic hoses, chemical injection hoses and electrical cables. Suspended (well) A well that has been capped-off temporarily.

T Taxa Categories in the biological classification system for all living organisms (i.e., kingdom, phylum, class, order, family, genus, species). Thermocline The vertical zone in the water column where temperature changes rapidly with depth. Tie-in An operation in pipeline construction in which two sections of line are connected; a loop tied into the main line. Topside The superstructure of a platform. U Umbilical A conduit through which hydraulic fluids, chemicals, power and data are supplied (see subsea control umbilical). Univariate Describes a collection of procedures which involve observation and analysis of one statistical variable. V Vibrocore Acquisition of seabed sediment cores using a vibrating steel tube which penetrates the seabed to a particular depth. W Water Cut The proportion (by volume) of produced water in the total fluids from a well. Water Injector A well in which filtered and treated seawater is injected into a lower water-bearing section of the reservoir, the primary objective typically being to maintain reservoir pressure. Well Head The surface termination of a wellbore that incorporates facilities for installing casing hangers during the well construction phase. The wellhead also incorporates a means of hanging the production tubing and installing the Christmas tree and surface flow-control facilities in preparation for the production phase of the well. Well-Test A test whereby the nature and quantity of the formation fluids in a possible oil- or gas-bearing stratum are determined by allowing them to flow to the surface through the drill string under carefully controlled conditions. X Xmas Tree An array of pipes and valves fitted to a production wellhead to control the flow of oil or gas and prevent a possible blow-out. Z Zooplankton Small aquatic animals that float or weakly swim within the water column. Generally longer than 153 µm, up to about 5,000 µm (5 mm).

ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

1 INTRODUCTION

EnQuest Heather Limited wishes to develop the Galia field in the UK Central North Sea (CNS). The field, located in UK continental shelf (UKCS) Block 30/24 in a water depth of approximately 80m, will be developed through a single production well (targeting the Fulmar reservoir) tied-back via a new oil production flowline to the nearby Alma production centre. The Alma production centre is in turn tied-back to the EnQuest Producer (formerly known as the Uisge Gorm) floating production, storage and offloading facility (FPSO). This Environmental Statement (ES) has been prepared to meet the requirements of United Kingdom (UK) legislation and in support of the Galia field development plan. It covers:

Drilling of a single production well;

Installation of a 5.3km 8” production flowline, power cable and control umbilical;

The increase of production at the EnQuest Producer FPSO; and

Operation and production of the field for an expected 10 years

1.1 THE DEVELOPER

EnQuest Heather Limited (EnQuest) is an independent oil and gas development and production company with a geographic focus on the UK continental shelf (UKCS). The Groups’ asset portfolio comprises primarily producing assets and development opportunities, together with exploration and appraisal opportunities, all of which are located in the UKCS. It has working interests in the Alma, Don, Thistle, Deveron, Heather, Ivy and Broom oil fields. EnQuest believes that the UKCS represents a significant hydrocarbon basin in a low-risk region. The UKCS continues to benefit from an extensive installed infrastructure base and skilled labour to develop, operate and manage assets. EnQuest’s management has considerable experience of working in the UKCS region and is familiar with the regulatory authorities and competitive landscape. EnQuest Heather Limited owns a 100% stake of the equity of the Galia Field.

1.2 PROJECT OVERVIEW

As a redevelopment of the Duncan field, the Galia field will be a small oil development with a field life of ten years. The field is located in UKCS Block 30/24, 280km east of the nearest landfall on the UK coastline. It is approximately 22km south west from the Norway/UK international boundary (median line). The project location is shown in Figure 1-1 and the co-ordinates are given in Table 1-1.

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 1 02/05/2012 2°0'E 2°40'E 3°20'E 4°0'E

Block 30/24

Alma Production Centre

EnQuest Producer Galia Well FPSO

Alma Water Injection Centre 56°40'N 56°40'N

km 00.5 1 2 3 4

Janice Alpha 56°15'N 56°15'N 55°50'N 55°50'N

2°0'E 2°40'E 3°20'E

Legend Galia Field Development Environmental Statement Median line

Land Figure 1-1: Project Location

UKCS Block Date Friday, March 2, 2012 11:51:28

Galia Well Projection ED 1950 UTM Zone 31N Spheroid International 1924 EnQuest Producer FPSO Datum D European 1950 Alma Production Centre Data Source EnQuest, UKDeal, KISCA Alma Water Injection Centre Galia Production Flowline File Reference J:\P1459\Mxd\Environmental Statement\Galia ES\ Figure 1-1 Project Location.mxd Alma Production Flowine Alma Water-Injection Flowline Produced By Emma White Checked Reviewed By Louise Mann FPSO

Platform Well

Pipeline

Cable km © Metoc Ltd, 2011. Hydrocarbon Field NOTE: Not to be used for navigation 04 8 16 24 32 40 All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Table 1-1: Project co-ordinates Structure Easting (E) Northing (N) Latitude (N) Longitude (E) Proposed Galia drill centre - vertical well 480 775 6 227 0.15 56° 11' 08.85" 02° 41' 19.53" (GAL-1) Alma Production Centre 485 469 6 228 541 56° 12' 05.72" 02° 45' 56.84" EnQuest Producer FPSO 488 250 6 227 000 56° 11' 16.16" 02° 48' 38.45" Datum: WGS84

1.2.1 Field History & Development Approach

The Galia Field was initially developed as the Duncan Field by Hamilton Brothers Oil Company. It was in production from February 1982 until October 1992 when it was decommissioned in 1992 due to the low oil price prevalent at the time. The field produced a total of 18.7mmbbl from a Stock Tank Oil Initially in Place (STOIIP) of 47.7mmbbl, representing a recovery factor of 39%. Tuscan Energy proposed to redevelop the field as Dalmore Field during 2003, but the project did not materialise. EnQuest now plan to rename and redevelop the Duncan field as the Galia field. This is because it is now commercially viable to carry out the redevelopment due to the current and forecasted oil price and the UK small field reserve allowance. Galia is located on a NW-SE trending tilted fault block a few kilometres west of the Alma raised fault block. The Galia structure is approximately 1km wide and 5km long and contains hydrocarbons in Upper Jurassic Fulmar Formation sandstones, sealed by the overlying Kimmeridge Clay Formation. Water depth at Galia is in the region of 80m. EnQuest are proposing to tie Galia in with their Alma development for the following reasons;

The entire previous field infrastructure was removed during the Duncan decommissioning;

Galia is a marginal field situated adjacent to their proposed redevelopment of the Ardmore field (to be known as Alma); and

Tying in to the Alma manifold will be cost effective and minimise environmental impact. 1.2.2 Schedule

Drilling of the Galia well is scheduled to start in September 2012 and is expected to take three months. The production flowline, umbilical and power cable are planned to be installed between April and November 2013 although there is a possibility for early installation between August and October 2012. First oil is expected to be in third quarter 2013 and field life is anticipated to be ten years.

1.2.3 Construction

The production well will be drilled in five sections using a combination of water based mud (WBM) and oil based mud (OBM), with each section cement cased. WBM and associated cuttings will either be discharged at the seabed or returned to the drilling rig and discharged at the sea surface. All OBM and

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associated cuttings will be skipped and shipped to shore for processing and disposal. The well will be drilled from the Ocean Princess semi-submersible drilling rig. The rig is self-propelled and maintains station using eight anchors. Anchors will be limited to an established anchor pattern within 1,500m radius of each drill centre (Figure 5-3). The Galia production well will be fitted with dual electrical submersible pumps (ESP) to boost flow rates. One 5.3km 8" flowline will connect the Galia well to the Alma production centre. The production flowline, the control umbilical (used for tree control and monitoring well conditions) and power cable (to power the ESPs) will be individually trenched and backfilled. Concrete mattresses will be used for protection on the approach to the Galia tree and the Alma production manifold. Approximately 25 mattresses will be used at each end of each of the three trenches, with a total of 150 mattresses. The Alma production centre is tied-back to the EnQuest Producer FPSO.

1.2.4 Production

First oil from the field is currently expected in third quarter 2013. Production forecasts suggest the field will produce a maximum (high case) of 389 tonnes of oil per day (466m3d-1). Oil production from Galia over the life of the field is expected to be 1.42 million tonnes (1.7 million m3) (high case). The Galia production well is expected to have a high water cut and will be produced with the aid of dual ESPs. At the start of field life the Galia well is expected to flow dry for a few months. The water cut will then increase steadily, with an average water cut of 35% for the first three years, reaching a water cut of 75% after three years. As the reservoir declines the water cut will increase to approximately 90%. Galia will produce back to the FPSO via the Alma production centre. It is expected that a shuttle tanker will visit the FPSO once every two weeks to offload stored crude oil via a loading hose and tanker mooring system. Under normal operations all produced water (PW) from the Galia well will be added to that from the Alma wells and re-injected with treated seawater into the Alma water-injection wells. It is possible that PW may be discharged if one of the water-injection pumps fails, however the PW handling process onboard the FPSO will ensure oil in water (OIW) concentrations are below 30mgl-1. PW may also be discharged to sea in the event that production (from all wells) starts prior to the commissioning of the injection wells. EnQuest’s current schedule is to have both water injection (WI) wells available by September 2013 with first oil start up planned in October 2013. In the event that WI drilling operations are delayed and the FPSO is completed as expected or slightly ahead of schedule there is potential for wet oil to be produced to the FPSO, resulting in PW being discharged to sea. This is discussed in further detail in Section 5.3.4. The tie-back of the Galia development to the Alma development will not result in a substantial increase in emissions during production from power generation. The gas produced from Galia will supplement the gas produced from the Alma wells which will be used for power generation on the FPSO. Under normal

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operations the gas will be used to fuel the steam boilers and when there is insufficient gas the boiler will switch to burning crude oil. As the boilers will run on gas augmented by crude, gas will not normally be flared. 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. For the high production case, up to 93.5 million Sm3 of excess gas would need to be flared over field life. The base case flaring is about 53% of this figure. Section 5.3.6.1 details the emissions from flaring as a result of the Galia tie-back.

1.2.5 Decommissioning

Field life is expected to be ten years and therefore decommissioning and abandonment will occur around 2023. The arrangements for decommissioning the field will be developed in accordance with UK government legislation and international agreements in force at the end of field life. However, the development plan is based on the following assumptions (see Section 5-4):

Plug and abandon the well;

Removal of the conductor to below the mud line;

All subsea infrastructure e.g. flowline, umbilical, power cable and well head, will be removed;

Third party confirmation of seabed clearance; and

These requirements were considered in the design of facilities and during project planning.

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1.3 FORMAT OF THE ES

This ES is divided into the principal sections outlined in Table 1-2. Table 1-2: Structure of this ES Section Title Content - Non-Technical Summary The aim of the non-technical summary is to enable communication with those unfamiliar with the environmental impact assessment (EIA) process and terminology by summarising the key findings of the ES document in simple terms. 1 Introduction An introduction describing the developer and summarising the project. 2 Institutional, Policy and A description of the legislative frameworks which govern the project Regulatory Frameworks and the EIA. 3 Project Justification and This section justifies why the project is preferable to alternative Alternatives options elsewhere. It also describes the alternatives considered within the project. 4 Impact Assessment A description of the process followed when conducting the EIA. Methodology 5 Project Description and A description of the project in terms of the activities that will be Footprint undertaken and the emissions to air, sea and ground from the construction and operational stages of the project. 6 Accidental Events This section describes the types of accidental event that could occur during the construction and production phases of the project and presents a summary of the oil spill modelling undertaken to inform the EIA. 7 Impacts on Physical These sections describe the physical, biological and human Environment baseline environment in the project area and identify those activities 8 Impacts on Biological of the project that may interact with environmental receptors. They Environment evaluate and specify project impacts upon the individual receptors, describing them quantitatively wherever possible (in some cases 9 Impacts on Human only a qualitative assessment is possible) and in each case the Environment level of significance has been determined. Mitigation measures to avoid, reduce or remedy the effects identified in the impact assessment are outlined. 10 Cumulative and Indirect This section considers cumulative impacts where the project Impacts contributes to impacts occurring from other activities or processes. 11 Environmental Management This section describes the EnQuest corporate and project specific management system outlining how EnQuest will manage health, safety and environment activities arising from the project. 12 Conclusions - 13 References - A Appendix A This section contains the environmental impact assessment tables. B Appendix B This section contains the description of the oil spill modelling carried out for the Galia development and its associated impacts. C Appendix C This section contains a summary of chemicals that could be used for the construction of the Galia development. D Appendix D This section contains the description of the environmental legislation

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1.4 ES AVAILABILITY

A digital or hard copy of the ES is available on request from:

Burton Millar EnQuest Senior HSE Advisor, Projects Level 5, Consort House Stell Road Aberdeen AB11 5QR

Email: burton.millar@enquest.com

The ES can also be downloaded from the Press Releases area at www.metoc.co.uk.

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2 INSTITUTIONAL POLICY AND REGULATORY FRAMEWORK

2.1 INTERNATIONAL CONVENTIONS, EC LAW, UK LAW AND POLICIES

Offshore oil and gas developments are governed by a collection of international, European Commission (EC) and UK laws, policies and guidelines. The management goals and objectives that an environmental assessment is required to achieve are governed by these laws/policies and the associated institutional frameworks. Although not an exhaustive list, Table 2-1 outlines the main policies, laws and guidelines relevant to this project and considered in this ES. Further details of each policy, law and guideline are provided in Appendix D. Table 2-1: Summary of international conventions, EC law and UK law and policy relevant to the project

Meeting the Energy Challenge 2007

UK Policy and UK Low Carbon Transition Plan 2009 Guidelines UK Marine Policy Statement 2011

UK Biodiversity Action Plan (UKBAP) 1992

Convention for the Protection of the Marine Environment of the North East Atlantic (Oslo Paris Convention (OSPAR) Convention) 1992

International Convention on Biological Diversity (CBD) 1992 Conventions United Nations Framework Convention on Climate Change (1994)

Convention on Environmental Impact Assessment in a Transboundary Context (Espoo) 1991

Council Directive 97/11/EC (EIA Directive)

Council Directive 2003/35/EC (Public Participation Directive)

Council Directive 2001/42/EC (SEA Directive)

Council Directive 92/43/EC (Habitats Directive)

Council Directive 79/409/EC (Birds Directive) EC Law Council Directive 2008/1/EC (Integrated Pollution Prevention and Control (IPPC) Directive)

Council Directive 2003/87/EC (EU Emissions Trading Scheme (EU ETS) Directive)

Council Regulation 1907/2006 Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH)

OSPAR Recommendation 2010/5 on the assessment

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of environmental impacts on threatened and/or declining species

Petroleum Act 1998

Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007

Offshore Petroleum Activities (Conservation of Habitats) Regulations 2001 (amended in 2007)

Offshore Marine Conservation (Natural Habitats, &c.) Regulations 2007 (as amended in 2009 and 2010)

Offshore Petroleum Activities (Oil Pollution Prevention and Control) Regulations 2011

Offshore Chemical (Amendment) Regulations 2011 UK Law Merchant Shipping (Oil Pollution Preparedness, Response Co-operation Convention) Regulations 1998

The Offshore Installations (Emergency Pollution Control) Regulations 2002.

The Merchant Shipping (Prevention of Pollution by Sewage and Garbage from Ships) Regulations 2008

Marine and Coastal Access Act (MCAA) 2009

Energy Act 2008

The Greenhouse Gas Emissions Trading Scheme Regulation 2005 (as amended)

The Offshore Combustion Installations (Prevention and Control of Pollution) (Amendment) Regulations 2007

2.2 SEA AND EIA GUIDELINES

The DECC have issued guidance notes regarding the Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007, providing details of the required contents of an ES. This ES takes into account this latest guidance (DECC 2011a). The EIA process considers the potential impacts from an individual project, ignoring those from other activities in the area. Although consideration is now being given to cumulative impacts in EIA, this is still project specific. As a result of the limitations of the EIA process there is a need to assess impacts at a more strategic stage of the industry development phase. SEAs consider environmental objectives at policy and planning stages, provide a common basis for EIA preparation, and ensures that total activity level in one region does not impose unacceptable regional environmental impacts. In 2001 the EC adopted a Directive on the assessment of the effects of certain plans and programmes on the environment 2001/42/EC (SEA Directive). Although the UK has yet to formally implement this Directive, the DECC has produced a series of SEAs for regions of the UKCS. This project lies within

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SEA region 2. Once SEAs were completed for all regions of the UKCS an Offshore Energy SEA (OESEA) was undertaken in 2008/2009 to inform further seaward rounds of oil and gas licensing, future licensing for the underground storage of combustible gas in depleted and other offshore oil and/or gas fields and further rounds of offshore wind farm leasing. This OESEA was updated with amendments and was re-issued in 2011. The technical reports and recommendations made in all of these SEAs were used to inform this EIA.

2.3 UK INSTITUTIONAL FRAMEWORK

Secretary of State (SoS) – The ES review and approval process culminates in an approval from the SoS under the Petroleum Act 1998. The SoS is also the focal point for appeals to decisions and leads the various teams in the DECC.

The Department of Energy and Climate Change (DECC) – Administers the Petroleum Act 1998 under which project consents are given. It is the principal environmental regulator for the offshore oil and gas industry and is responsible for implementation of the EIA Regulations. The DECC also represent the UK as a Regulatory Authority at OSPAR.

Department for Environment, Food and Rural Affairs (Defra) – Responsible for implementation of Government programmes for the protection of the environment, food (including fisheries) and rural affairs. At the European and international level Defra represent the UKs interests at OSPAR. The department provides advice to the DECC on a range of subjects including: environmental statements; the interactions between fisheries and offshore operations; offshore construction and drilling activities; marine pollution; and chemical use and discharge. In England many of the advisory responsibilities for the offshore oil and gas industry are delegated to the Centre for Environment, Fisheries and Aquaculture Science (Cefas).

Joint Nature Conservation Committee (JNCC) – Responsible for promoting nature conservation at UK and international levels. They are the main government and industry advisor on offshore sensitivities with respect to seabirds and cetaceans. Amongst other roles they advise the DECC on ESs and are the body responsible for identification and recommendation on offshore conservation areas under the EC Habitat Directive.

Cefas – Is the executive agency of Defra responsible for the integrated management of the UK’s sea (excluding Scotland). Amongst other roles Cefas advises the DECC on the Offshore Chemical Regulations and impacts on fish and fisheries.

Marine Scotland - Performs a similar role to that of Cefas but for Scottish waters. Whilst the Galia development is not located in Scottish waters, it is close enough for Marine Scotland to be considered as a consultee.

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2.4 ENQUEST CORPORATE POLICY

EnQuest policy is to conduct its operations in a responsible manner that protects the health and safety of people and minimises the impact on the environment. EnQuest’s commitment with respect to environmental issues is laid down in the Health, Safety, Environmental and Quality Policy, presented as Figure 2-1. The policy is reviewed annually by the HSEQ team and communicated to all persons working on behalf of the organisation. EnQuest maintains a comprehensive HSE management system, details of which are provided in Section 11.

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Figure 2-1: EnQuest HSEQ Policy

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3 PROJECT JUSTIFICATION AND ALTERNATIVES

3.1 PROJECT JUSTIFICATION

Ignoring short-term fluctuations, it is broadly accepted that energy demand is growing, both nationally and internationally. It is also likely that for some time to come the energy demand will be met largely by fossil fuels such as oil, gas and coal (DTI 2007). In 2010, the UKCS oil production was enough to satisfy 87% of domestic consumption, produced mainly from fields in the CNS basin, with some production in the Northern North Sea (NNS) and Southern North Sea (SNS). Having access to its own reserves has contributed greatly to the UK’s wealth (OGUK 2011). This security of supply has also enhanced the UK’s self- sufficiency in the international arena, particularly at a time when increased competition for resources and global economic uncertainty is leading to high fluctuations in energy markets and fuel costs. UK oil production peaked in 1999 and is currently declining. Production averaged 0.9 billion barrels of oil equivalent in 2009, a decline of nearly 10% from 2008 production figures (OGUK 2009). In 2020, 60% of the UK’s primary energy will still come from oil and gas, even if the UK’s target to achieve 15% energy from renewable sources1 is achieved. If investment is sustained, the UKCS has the potential to satisfy 60% of the UK oil and gas demand in 2020 (OGUK 2011). Clearly, as consumer demand increases and production continues to decline, at some stage in the future the UK will switch to being a net importer. 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 2011b). 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 development of the Galia Field is part of this strategy and would bring on-stream a marginal field that it is now economically feasible. As stated above, UK oil production for 2009 was 900 million barrels of oil equivalent (123 million tonnes) (OGUK 2010). Assuming the 10% decline in production noted earlier continues, current annual decline in production is approximately 90 million barrels (12.3 million tonnes) per year.

1 The European Council agreed in 2007 to a binding agreement that sets a target for 20% of the EU’s energy to be from renewables by 2020. The UK Energy White Paper commits the UK to see renewables grow as a proportion of the UK electricity supply to 10% by 2010, with an aspirational level of 20% by 2020 (DTI 2007)

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Current estimates are that, based on a 10 year field life, the low case recovery from the Galia field will be 0.880 million tonnes (1.054 million m3), 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). The cumulative production profiles for all cases are shown in Table 3-1. Table 3-1: Cumulative (by year) production profiles Low Case Base Case High Recovery Year Tonnes Tonnes Tonnes m3 (x106) m3 (x106) m3 (x106) (x106) (x106) (x106) 2013 0.085 0.101 0.087 0.105 0.174 0.209 2014 0.327 0.391 0.42 0.503 0.85 1.017 2015 0.453 0.543 0.547 0.655 1.107 1.326 2016 0.554 0.664 0.615 0.736 1.244 1.489 2017 0.640 0.766 0.655 0.784 1.312 1.571 2018 0.713 0.854 0.681 0.816 1.352 1.619 2019 0.772 0.924 0.952 1.139 1.377 1.649 2020 0.812 0.972 1.048 1.255 1.395 1.67 2021 0.840 1.006 1.099 1.316 1.407 1.684 2022 0.862 1.033 1.127 1.35 1.415 1.694 2023 0.880 1.054 1.144 1.37 1.42 1.7 Source: EnQuest 2011a The Galia development meets 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 The purpose of this project is to develop a marginal field using a cost effective solution, in order to deliver oil to the UK. The development has been designed to minimise risks to people and the environment. EnQuest’s participation in North Sea oil and gas exploration and production also contributes towards achieving the national objectives to prolong indigenous production, and to attract new independent companies into the North Sea.

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3.2 PROJECT ALTERNATIVES

The consideration of alternatives to a proposed project is a requirement of many EIA processes and a standard requirement of the Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007. A comparison of alternatives helps to determine the best method of achieving the project by indicating the best available technique (BAT) or the best environmental practice (BEP). The type and range of alternatives considered might include:

Supply or activity alternatives e.g., alternative means of achieving project goal (i.e. energy supply) irrespective of location

Location alternatives, either for the entire project or for individual components e.g., the siting of a platform or the routing of a pipeline

Process or infrastructure alternatives e.g., use of waste-minimising or energy-efficient technology, establishing new infrastructure or using existing facilities

Scheduling alternatives e.g., to avoid sensitive periods of the year for particular environmental receptors The World Bank recommends a tiered approach to the analysis of alternatives. It is designed to bring environmental considerations into all stages of development planning and ideally begins with strategic environmental assessment (SEA) to analyse broad alternatives within a region (Sadler and McCabe 2002). In the UK, a set of SEAs are in place which fulfils this purpose. This section discusses:

The alternatives to the proposed project (Section 3.2.1) i.e., why the development of an oil project is considered the best alternative for the area in relation to the UK energy strategy

The alternatives that were considered within the project (Section 3.2.2) e.g., location, process, infrastructure and scheduling alternatives. 3.2.1 Alternatives to the proposed project

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 technology such as wind. As such, the development of the field is considered to be the best option for providing a new energy source.

3.2.2 Alternatives within the proposed project

EnQuest has investigated a range of development options for the following project elements:

Production system

Drilling rig

Production flowlines These are tabulated below, (Table 3-2) highlighting advantages and disadvantages with respect to technical, economic and environmental considerations.

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Tie-in with the proposed Alma development was selected as the best production option. For a small development with a relatively short field life such as Galia, the ability to utilise an existing production facility is a key factor - on both economic and environmental grounds.

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Table 3-2: Advantages and disadvantages of different development scenarios Option Advantage Disadvantage Decision 1A: Tie in to Proximity of the in-situ EnQuest Producer FPSO to None identified Selected the Alma the Alma production centre and ease with which the development & Galia well can be tied back use of EnQuest Alma production manifold has a spare slot for Galia Producer production flowline FPSO Minimises seabed infrastructure

Utilisation of existing facility and avoidance of new build environmental impacts FPSO owned and operated by EnQuest therefore minimising interfaces Lower Capital Expenditure (CAPEX) costs than for provision of own facilities Lower Operational Expenditure (OPEX) costs than for provision of own facilities 1B: Provision Systems designed specifically for field Not a viable option for just one well due to higher Rejected of own New facility and equipment designed for field life CAPEX costs (platform/FPSO) production Latest technology designed into build Limited pipeline export routes (platform) facilities (i.e. Platform has large seabed footprint FPSO/platform) Definitive build cost Jacket structure would require substantial piling operations (platform) Would require substantial decommissioning at end of field life (platform) Limited pumping capacity before storage limit is reached (FPSO)

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Option Advantage Disadvantage Decision 2A: Semi- Ocean Princess semi-submersible already under None identified Selected Submersible contract and on location at the neighbouring Alma Drilling Rig field

2B: Heavy Lower operation day rates Lower lifting and storage capacity Rejected Duty Jack-up Potentially lower waiting on weather once located on Rig availability tighter than for semi-submersibles Drilling Rig site Spud can disturbance could affect future rig Potentially smaller seabed footprint (only area of locations spud cans) Would require additional geotechnical site investigations for spud can placement which could not be covered under Galia surveys in 2010 Jack-up may experience problems with horizontal xmas tree 3B: Buried Greater protection for flowlines – no additional Larger seabed footprint than surface laid option Selected flowlines protection such as rock would be required except for If selecting low temperature option for flowlines then mattressing and grouting at trench transition areas flowlines could not be protected or buried Conventional / proven solution As the flowlines would run quite hot, there would be Lower fishing impacts a potential requirement for large cooling spools if trenched Harder to decommission. It is more likely that the pipeline would have to be left in-situ at end of field life Higher mobilisation costs for installation as would need more vessels and equipment

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Option Advantage Disadvantage Decision Higher risk of subsurface obstructions during trenching which would need to be micro-routed Surface protection needed where spans can not be buried due to substrate/obstructions. 3A: Surface Ease of installation – range of installation vessels Greater risk of damage Rejected laid flowlines available. Higher procurement costs than trenched flowlines Benefit as compact field layout with possible drilling May require dropped object protection e.g. rock rig on site during installation material, concrete mattresses, which will increase Lower mobilisation costs for installation seabed footprint Potential of re-use / decommissioning easier Conventional / proven solution Minimal seabed disturbance Lower risk of subsurface obstructions because no trenching Less than 1m of silty sand as surface layer. Flowlines may sink in to sand offering protection during the project life.

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4 IMPACT ASSESSMENT METHODOLOGY

4.1 ENVIRONMENTAL AND HUMAN IMPACT ASSESSMENT PROCESS

The EIA process comprises six stages:

Project definition, understanding how environmental considerations have formed an essential part in the development concept, definition and selection of activities (Sections 3, 5 and 6 )

Scoping of potential impacts and information collection on environmental conditions (Sections 4.1.4.1, 7, 8, and 9)

Prediction and assessment of potential impacts (Sections 7, 8 and 9)

Development of management and mitigation measures (Sections 7, 8 and 9)

Residual impact significance assessment (Sections 7, 8 and 9)

Communication and reporting of results These steps are informed by the assessment team, the project engineering and management team and by stakeholder consultation throughout the EIA process as shown in Figure 4-1. Further details of the stakeholder engagement process undertaken for the Galia field and its contribution to the project are provided in Section 4.3. Figure 4-1: Overview of EIA methodology

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4.1.1 Project Definition

The first stage of the EIA process is to establish a detailed understanding and description of the project and its associated emissions, effluents and physical footprint. EnQuest’s project engineers and contractors have defined project activities relating to construction, commissioning, operations and decommissioning of the Galia field, which are presented as the Project Description (Section 5). Working with the project engineers, the assessment team has calculated the footprint of the project on the environment (Section 5), by quantifying emissions to air, water and the seabed. Where it has not been possible to establish a quantitative footprint, qualitative methods have been used.

4.1.2 Establish Baseline Environment

The environmental and human conditions at the site need first to be identified in order to assess project impacts. These have been divided into the three categories below:

The physical environment (Section 7)

The biological environment (Section 8)

The human environment (Section 9) A baseline for each of these has been established using combination of primary and secondary data sources. Primary sources are those which originate from site specific field studies and secondary sources are those taken from a range of research sources e.g., acquired from appropriate agencies or from published literature. The data sources used to describe each environmental or human receptor are listed at the beginning of each baseline sub-category in Sections 7, 8 and 9. A summary of the primary and data acquired for the project is provided below. It should be noted that the following assumptions were made when establishing the project environmental baseline:

Third party and publicly available information is correct at the time of publication

Baseline conditions are accurate at the time of physical surveys (accepting that the dynamic nature of the environment, conditions may change during the construction, operation and decommissioning phases of the development)

The development, including surrounding area, will not be subject to unforeseen events of a severe nature Primary Data A site survey was carried in June 2011 by Gardline Geosurvey (GGL 2011). Geophysical (high resolution seismic, single beam and multi-beam echo sounding, sidescan sonar, magnetometer, pinger, boomer and mini airgun), geotechnical (vibrocore and Cone Penetrometer Test (CPT)) and environmental (grab sampling and still photography) data were collected as listed below and shown in Figure 4-2.

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A 5.7km x 4.7km anchoring conditions survey covering three possible locations for the Galia well, with an extension to the south measuring 3.1km x 1.8km to cover two additional possible well locations

6km pipeline survey (Alma northern drill centre to Galia)

6km pipeline survey (Alma southern drill centre to Galia)

A 1.9km x 1.5km well site survey incorporated the five possible locations for the Galia well. The aim of the survey campaign was to:

Characterise the seabed and shallow geology in terms of topographical conditions, shallow geological and seabed features, sediment type and sediment particle size distribution

Identify obstructions and debris on the seabed

Characterise the anchoring conditions

To provide a top hole prognosis for the five surveyed proposed well locations

Characterise the benthic community

Characterise the sediment conditions

Determine whether any features of conservation importance are present, including any Potential Annex 1 habitats protected under the UK’s Offshore Marine Conservation (Natural Habitats, & c.) (Amendment) Regulations 2010; those on the OSPAR (2008) list of threatened and/or declining species and habitats, and those listed as priority species and habitats in the UK Biodiversity Action Plan

All data acquired are considered to be of good quality and sufficient resolution to identify physical and biological features of importance, if present.

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ENV5 ENV4 ENV11 56°12'N 56°12'N ENV9 ENV8

ENV1

ENV3 ENV2

ENV6 ENV10

ENV7 56°9'N 56°9'N

2°39'E 2°42'E 2°45'E 2°48'E

Legend Galia Field Development Environmental Statement Figure 4-2: Galia development survey extents Galia Well

Uisge Gorm FPSO Date Thursday, October 27, 2011 17:31:01 Alma Northern Drill Centre Projection ED 1950 UTM Zone 31N Alma Southern Drill Centre Spheroid International 1924 Galia Production Flowline Datum D European 1950 Alma Production Flowline Data Source Gardline, UKDEAL Alma Water-Injection Flowline File Reference J:\P1459\Mxd\GALIA\ Galia_Survey_Area.mxd Environmental Baseline Station Anchoring Conditions Survey Area Produced By Emma White Checked Relief Well Survey Area Reviewed By Anna Farley

Land

NOTE: Not to be used for navigation km © Metoc Ltd, 2011. 0 0.5 1 2 3 4 All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

4.1.3 Identification of Project Aspects

Following collation of baseline information, the next stage of the EIA process is to determine the environmental aspects of the project. An environmental aspect is defined as “an element of an organisations activities, products or services that can interact with the environment” (BSI 2001). They are determined from systematic review of all project activities to establish potential (either directly or indirectly) to:

Breach relevant legal standards, corporate environmental policy and management systems

Interact with the existing natural environment including its physical and biological elements

Interact with the existing human environment

Cause significant stakeholder concerns. A summary of the project activity components are listed in Table 4-1. Table 4-1: Project activities Activities Activity Components Construction Presence of vessels (including drilling rig and support vessels) Drilling of wells Installation of subsea infrastructure e.g., flowline, umbilical, power cable and wellhead Production Increase in power generation on the FPSO as a consequence of Galia Start-up gas flaring (if necessary) Increased discharge of produced water from the FPSO as a consequence of Galia Use and discharge of chemicals Accidental Events Chemical and hydrocarbon release (> 1 tonne) Chemical and hydrocarbon release (1 - 10 tonnes) Chemical and hydrocarbon release (> 10 tonnes) Overboard loss of equipment or waste 4.1.4 Determination of Potential Impacts

4.1.4.1 Scoping

Based on their experience, an understanding of the project description, and the nature and extent of project aspects, the assessment team identified whether a project aspect had the potential to interact (positively or negatively) with the environmental receptors. These potential interactions were recorded in an Interaction Matrix, an extract of which is provided as Table 4-2. The completed Matrix is provided as Appendix A for reference.

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Table 4-2: Extract from the Galia issues interaction matrix Environmental Receptor Physical Biological Human

Project Aspect Atmosphere Atmosphere Water column Seabed conditions Plankton Benthic communities Fish and shellfish Seabirds Marine mammals sites Marine protected and species Archaeology fishing Commercial Oil andGas infrastructure Shipping users marine Other General Construction Physical presence and movement of drilling rig and support vessels Exhaust gas emissions

4.1.4.2 Prediction and Assessment of Potential Impacts

The diverse range of potential impacts considered in the EIA process means that a range of prediction methods need to be used to assess impact potential, including quantitative, semi-quantitative and qualitative methods. The impact prediction and assessment process took into account any mitigation or control measures that are part of the project design/project plan. Additional mitigation measures aimed at further reducing identified impacts are then proposed where necessary or as appropriate. Table 4-3 provides an example of an activity associated with the project, its aspects and potential impacts. Table 4-3: Example development activity, aspect and impact identification Project Vessel movements Activity Aspect Exhaust gas emissions Impact Localised deterioration in air quality

Once the impact has been identified, its significance is assessed using the following criteria:

Likelihood – How likely is an impact to occur as a result of an activity (see Section 4.1.4.4 and Table 4-4).

Severity – The severity or consequence of an impact is a function of a range of considerations (see Section 4.1.4.5 and Table 4-5). 4.1.4.3 Nature of Impacts

Several different types of impact are recognised in the assessment as described below:

Negative Impact - an impact that is considered to represent an adverse change from the baseline condition or introduces a new undesirable factor

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Positive Impact - an impact that is considered to represent an improvement on the baseline condition or introduces a new desirable factor

Direct Impact - impacts that result from a direct interaction between a project activity and the receiving environment (e.g., between occupation of an area of seabed and the habitats which are lost)

Secondary Impact - Impacts that follow on from the primary interactions between the project and its environment as a result of subsequent interactions within the environment (e.g., loss of part of a habitat affects the viability of a species population over a wider area)

Indirect Impact - Impacts that result from other activities that are encouraged to happen as a consequence of the project (e.g., project implementation promotes service industries in the region)

Cumulative Impact - Impacts that act together with other impacts to affect the same environmental resource or receptor 4.1.4.4 Likelihood of Impact Occurrence

The likelihood (probability) of an impact occurring has been defined using the qualitative scale of probability categories in Table 4-5. Likelihood is estimated on the basis of experience and/or evidence that such an outcome has previously occurred. Table 4-4: Assessment process for identification of potential impacts Likelihood Definition Very Unlikely Freak combination of factors required for event to occur.

Unlikely Rare combination of factors required for event to occur.

Possible Could happen with additional factors present. Likely Not certain. Additional factors may result in event. Very Likely Almost inevitable an event would result.

4.1.4.5 Impact Severity

In evaluating the severity (positive or negative) of environmental or human impacts, the following factors have been taken into consideration:

Duration of the Impact: how often the impact will occur and for how long will it interact with the receiving environment

Spatial Extent of Impacts: whether the impact effects the local, regional or wider environment

Sensitivity of Receiving Environment: the nature, importance (i.e., whether of local, national, regional or international importance) and the sensitivity or adaptability to change of the receptors or resources that could be affected. This also takes account of any laws, regulations or standards aimed at protecting the receiving environment

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Recoverability of Receptor: how long until the receptor will return to pre-impact condition. These are further defined in Table 4-5. Table 4-5: Severity definitions Term Value Definition Impact Duration Short 1 The interpretation of these descriptors varies according to the Moderate 2 impact topic. For example, a short term impact to the seabed, such as the effects of levelling works, may last for a year, Long 3 whereas a short term impact to water quality, such as effects from the discharge of water based mud, could involve a period Permanent 4 of 12 to 24 hours. Spatial Extent The primary zone of influence of the project. In this instance Local 1 the local region encompasses the area within a radius of 1 km around the project footprint. Impacts extend beyond project locality to impact on the region. Widespread 2 The region in this instance would encompass the CNS. Extensive 3 Impacts on a national scale (effects well beyond the CNS). Global 4 Impacts on a global scale (e.g., global warming). Sensitivity of Receiving Environment • Abundant/ common species/ environment and broadly distributed Low 1 • Robust in nature and proven to be adaptable to changing environments • Valued but not unique • Range/ abundance covers numerous regions • Under pressure but has some ability to adapt to Medium 2 changing environment • Valued locally as an important species or environment • Range/ abundance restricted to a limited number of areas • Under pressure and showing some, but slow, High 3 adaptability to changing environment • Valued regionally as an important species or environment • Rare/ unique species/ environment • Under significant pressure and likely to fail or be Very High 4 irreversibly damaged • Valued globally as an important species or environment Recoverability of Receptors Short 1 The interpretation of these descriptors varies according to the

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Term Value Definition Moderate 2 impact topic. For example, a long recoverability to plankton species, such as the toxic effects of a chemical discharge may Long 3 last a few months. Whereas a long recoverability to some fish species, such as removal of benthic breeding habitat, could Irreversible 4 involve a period of 10 to 20 years.

The outcomes from each of the above factors were then tallied to decide an overall grading value of the severity of a particular impact. Where quantification of potential impacts is possible, the decision has been based on numerical values, representing regulatory limits, project standards or guidelines (e.g., noise and air quality impacts). A number of environmental aspects such as ecology, landscape, visual and generally all human impacts require a more qualitative approach for determining severity. Semi-quantitative and/or qualitative methods have therefore been used whereby the criteria have been set according to severity factors as defined in Table 4-6 above. The severity factors have been scored with a numeric value from 1 to 4. The sum of values for each of the factors was used to determine the overall severity as summarised in the scale outlined below:

Negligible (sum of values 4 - 6)

Low (sum of values 7 - 9)

Medium (sum of values 10 – 12)

High (sum of values 13 – 16) 4.1.4.6 Assessing Impact Significance

For the potential impacts associated with the Galia field development, the significance of each impact is determined by assessing the impact severity against the likelihood of the impact occurring as summarised in the impact significance assessment matrix provided in Table 4-6. It is important to emphasise that the resulting significance from these two elements is not the likelihood of the activity occurring, but rather it is the likelihood of that activity causing the impact described. Table 4-6: Environmental and human impact significance assessment matrix Likelihood Severity Very Very Unlikely Possible Likely Unlikely Likely Negligible (4 -6) Insignificant Minor Minor Minor Minor Low (7 - 9) Minor Minor Minor Moderate Moderate Medium (10 – 12) Minor Minor Moderate Moderate Major High (13 – 16) Moderate Moderate Moderate Major Critical

Based on the outcome of the significance assessment the following points need to be considered:

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Critical Significance

It is not possible to manage or mitigate critical impacts. These require the identification of alternatives (elimination of source of potential impact). Such impacts are intolerable and could potentially result in abandonment of a project. Major Significance

Check that the residual impact has been subject to feasible and cost effective mitigation where possible

Where no further reduction in impact levels can be made, it remains a high-level impact and which may therefore be subject to offsets Moderate Significance

Check that the residual impact has been subject to feasible and cost effective mitigation and that no further measures are practicable Minor Significance

Not mitigated further An assessment of the significance of the impacts from the project was undertaken and the results are presented in the technical assessment sections (Section 7 to 9) to follow and Appendix A.

4.1.5 Mitigation of Potential Impacts

Mitigation measures are the actions or systems that are used, or have been proposed, to manage or reduce the potential negative impacts identified. They may also be used to enhance the positive benefits, especially in relation to human issues. They are applied using the following mitigation hierarchy:

Avoid at Source/Reduce at Source: essentially designing the project so that a feature causing a potential impact is designed out or altered.

Abate on Site: adding something to the basic design to abate the potential impact – pollution controls fall within this category.

Abate at Receptor: if a potential impact cannot be abated on-site then measures can be implemented off-site.

Repair or Remedy: some potential impacts involve unavoidable damage to a resource. Repair involves restoration and reinstatement measures.

Compensate/ offset: replace in kind or with a different resource of equal value Mitigation is an integral part of the Galia development. All of the potential impacts identified from this project are subjected to either standard recognised best practice mitigation measures or to impact specific, feasible and cost effective mitigation. The mitigations measures considered pertinent for each environmental and human issue considered are outlined in the individual technical sections to follow, are summarised in Section 10 and detailed in Appendix A.

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4.1.6 Residual Impact Assessment

Residual impact is the remaining or mitigated impact level after all avoidance, design and management measures have been taken into account. If the risk assessment determined that after mitigation measures were applied there would be no residual impact no further assessment was undertaken on the impact. If, however, it was concluded that a residual impact may still be expected the impact assessment was re-conducted starting with an assessment of the likelihood and severity, to determine the significance of the residual impact The results of the residual impact assessment are presented in the technical assessment sections (Section 7 to 9) to follow and Appendix A.

4.2 CUMULATIVE AND INDIRECT IMPACTS

In accordance with the EIA regulations, the EIA has given consideration to cumulative and indirect impacts and interactions. The definitions of these three types of impact overlap. For the purposes of this assessment, the definitions proposed by the European Commission (1999) have been used. The definitions are as follows:

Indirect Impacts – Impacts on the environment, which are not a direct result of the project, often produced away from or as a result of a complex pathway. These are sometimes referred to as secondary impacts. An example of an indirect impact is the impact on commercial fish landings as a consequence of the poor stock recruitment because seabed disturbance has caused the loss of spawning grounds.

Cumulative Impacts – Impacts that result from incremental changes caused by other past, present or reasonably foreseeable actions together with the project. Cumulative impacts can either be the interactions of the same type of activity within:

A single current project e.g., habitat loss caused by pipeline trenching added to the habitat loss cause by the installation of subsea structures leading to an overall larger area of habitat loss than one activity on its own.

Two projects in the same area whether this be historic, future, or a different industry e.g., habitat loss caused by the Galia field development combined with the habitat loss caused by the decommissioning of the previous fields combined with the habitat loss of trawling leading to an overall larger area of habitat loss

Impact Interactions – The reactions between impacts whether between the impacts of just one project or between the impacts of other projects in the area. For example, the discharge of oil in produced water and the discharge of chemicals could individually not have an impact on water quality but combined could mean quality deteriorates past threshold levels.

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Impacts considered in this ES relate to impacts due to the project and:

Other activities within the project

Other oil and gas projects (past, present and future)

Other seabed users e.g., commercial fishing, wind farms, marine aggregate extraction

Climate change e.g., changes in sea level One of the objectives of the SEA process was to strategically address cumulative impacts from oil and gas projects on a regional scale. In accordance with the EIA regulations it evaluates "any direct or indirect effects (including secondary, short, medium and long-term, permanent and temporary, positive and negative effects) resulting from the existence of the activity, the use of natural resources and the emission of pollutants, the creation of nuisances and the elimination of waste". Section 10 presents, quantitative assessments of the cumulative and indirect impacts and interactions (where possible), qualitative descriptions of impacts including the spatial and temporal scope of the assessments and a discussion of which impacts have not been addressed and why.

4.3 EIA STAKEHOLDER CONSULTATION

Although not a statutory requirement, it is recognised best practice that EIA methodology should also include stakeholder consultation. Early consultation can often be a critical first step to the development of a comprehensive and balanced EIA, especially in areas of heightened sensitivity both environmentally and from a human perspective. Views of the interested parties serve to focus the environmental studies and identify specific issues which require further consideration. Figure 4-1 presents a graphical depiction of the process followed and identifies that stakeholder consultation is a key component to the whole process. Consultation for Galia was undertaken as a part of the consultation for the Alma development as at the time it was planned to develop Galia and Alma as one field. Through previous project experience and consultation with the authorities, the key stakeholders identified for the Galia field development are the same as for Alma; the DECC, the JNCC, Marine Scotland and the Scottish Fishermen’s Federation (SFF). Responses and advice from all consultees have been incorporated into project planning.

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5 PROJECT DESCRIPTION AND FOOTPRINT

This section includes the project schedule, project description, project footprint and an activity summary. The project schedule provides an outline of the likely timetable over which the main project activities will be performed. The project description and project footprint are organised by the key elements or main stages of the Galia Field development, which are:

Drilling of one production well

Tie back to the Alma production centre through installation of one 8" production flowline, one control umbilical and one power cable

Changes in production at the EnQuest Producer FPSO as a direct consequence of the Galia field

Operation and production of the field for an expected 10 years The project description covers activities to be undertaken during construction, commissioning, production and the decommissioning of the development after the end of production life. It provides the basis upon which the prediction and evaluation of the environmental and human impacts has been conducted. The project footprint includes the physical presence of the project on the surrounding environment (e.g., drill cuttings, anchor scars and pipeline trenching on the seabed) and emissions to air and water (e.g., greenhouse gas emissions to the atmosphere, chemical and wastewater discharges to sea and noise pollution to air and sea). For each main stage a quantitative (where possible) and a qualitative summary of the environmental footprint of the project on:

The atmosphere

Water resources

The seabed

An overview of the field development is shown in Figure 5-1 below.

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Figure 5-1: Galia field development

Source: EnQuest 2011 Note: Diagram for illustrative purposes only and does not necessarily reflect exact layout of flowlines and associated infrastructure.

5.1 SCHEDULE

Construction at Galia is scheduled to commence in September 2012 with the drilling of the well. The flowline, umbilical and power cable will be installed and commissioned in an 8 month window between April and November 2013, although there is a possibility of early installation between August and October 2012. Field commissioning is expected to take place between February and May 2013, with first oil is expected in October 2013 (Table 5-1). Table 5-1: Project schedule Activity 2012 2013 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Drilling Flowline installation Field commissioning First oil

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5.2 CONSTRUCTION

Construction activities are generally well defined and described below. Minor changes, if any, will be captured by the PON15 process.

5.2.1 Well project description

The Galia well will be drilled from the Ocean Princess semi-submersible (semi- sub) mobile drilling unit (MoDU) and will be suspended pending tie-in to the production flowline and the Alma production centre. It is expected that the well will take three months to drill and complete. A preliminary list of chemicals to be used during drilling is supplied for reference in Appendix C. The exact formulation to be used for the well will be finalised in a PON15B application submitted to the DECC at least 28 days prior to drilling

5.2.1.1 Drilling Rig

EnQuest plan to use the Ocean Princess semi-sub, which is already on location at Alma. The Ocean Princess (Figure 5-2) is approximately 61m x 70m x 37m (topside) with an operating draft of 22m. It is capable of operating in depths up to 558m, drilling to depths of 7,620m and has the berth capacity for 100 personnel. A 500m safety exclusion zone will be established around the rig enforced by a guard/standby vessel on a 24 hour basis. Figure 5-2: Ocean Princess semi-submersible drilling rig

Source: www.diamondoffshore.com The following support systems and services are located on the rig:

Bulk storage – is provided for fuel oil, bulk drilling mud and cement, liquid drilling fluids, drill water and potable water

Pipe and materials storage – covered storage is provided for sacked material, drilling equipment, spares etc, and deck storage for drill pipe casing

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Helideck and craneage - for loading/off loading personnel, equipment and supplies

Environmental protection – sewage treatment unit and hazardous and non-hazardous drainage systems, which collect rainwater and/or any minor spills to a drains tank prior to discharge to sea, or allow transfer to tote tanks for shipment to shore and disposal by licensed waste disposal contractors The rig is self-propelled and maintains station by using anchors. Anchors will be limited to an established anchor pattern within 1,500m radius of the drill centre (Figure 5-3). The rig is expected to use eight 12 tonne Bruce MK-4 anchors in a catenary system. In this anchor system, the anchor chains rest on the seabed and can scour when made to move due to weather conditions.

5.2.1.2 Well design

The Galia production well will be drilled in five sections (36", 26", 17½", 12¼" and 8½"). The 36" section will be drilled as an open hole using water based mud (WBM) with all cuttings being discharged directly to the seabed. A 30" conductor will be run and cemented into place to support the hole walls. The 26" section will then be drilled with WBM with cuttings also being discharged directly to the seabed. Once complete a 20" casing will be cemented in to the hole and a marine riser installed to allow all further cuttings and drilling fluids to be returned to the rig. The 17½" section will either be drilled with WBM or oil based mud (OBM). If WBM is used then cuttings will be discharged to sea from the rig after passing over the shale shakers. Once the 17 ½" hole section is complete the 13 ⅜" casing will be run and cemented into the wellbore. The 12¼" and 8½" sections will both be drilled using OBM. The 12 ¼" section will be lined by a 9 ⅝" casing and the 8 ½" hole section will be lined with a 7" liner. OSPAR Decision 2000/3 prevents the discharge of OBM to the marine environment. Therefore, all returned OBM fluids and associated drill cuttings will be collected and skipped and shipped for thermal treatment onshore. Drilling muds have five primary purposes:

To remove the cuttings (produced by the drill bit) from the formation and carry them to surface

Lubricate and cool the drill bit during operation.

Maintain hydrostatic pressure so that gas and fluids from the formation do not enter the well bore causing a kick or blow-out.

Build a filter cake on the hole wall to prevent fluid loss to the formation.

Support and prevent caving of the wall of the hole. The drilling rig circulates the mud by pumping it through the drill string to the drill bit. From here it travels back up the annular space between the drill string and the sides of the hole being drilled. The circulating system is essentially a closed system with the mud recycled throughout the drilling of the well. Various products may be added to make up for losses (to formation), to adjust the mud’s properties, or to overcome difficult conditions (e.g., stuck drill pipe or loss of well pressure of fluid). Shale shakers are a vibrating sieve that drilling fluid and cuttings pass over. The liquid phase of the mud passes through the screen wire mess whilst the

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larger solids including the drill cuttings are retained on the screen and eventually fall off the back of the shaker. The fluids are recycled back into the drilling system whilst the retained solids and drill cuttings are discharged from the rig via a cuttings chute that is typically positioned 1m to 10m below the water line (if WBM is being used).

5.2.1.3 Cementing

Casing is cemented into place in all the sections of the well bore down to the interface with the reservoir. As each diameter section of the well bore, is finished, sections of metal casing, slightly smaller than the well bore diameter are placed in the hole to provide structural integrity. These are cemented in to place by pushing cement in the space (annulus) between the casing and the borehole. The cement fluids are pre-mixed in pits on the drilling rig before being pumped downhole. To minimise the quantities of chemicals pumped down hole, a cement liquid additive system will be used to calculate the volumes of premixed fluid required for the job. It is possible that some cement may remain in the mix water pit after the operation, or circulate out from the liner top after installation. These volumes are known as dead volumes. The disposal route for dead volumes is dilution prior to discharge to sea. It is desirable that the dead volumes are below 10%. Depending on the operation and type of chemical to be used this can be increased to a maximum of 30%. Any significant quantities of mix fluids will be skipped and shipped to shore.

5.2.1.4 Completion

The well will be completed with components and tubing which are designed to last the life of the well within acceptable corrosion limits. The completions will include the necessary hardware for the location, operation and power supply for the downhole ESPs.

5.2.1.5 Well bore clean-up

On completion of the 8½" section, the wellbore will be cleaned-up to remove residual quantities of OBM from the casing before the wellbore is suspended by displacing it to inhibited seawater. The clean-up will involve a 60bbls (9.5m3) spacer / detergent mix being circulated in front of the inhibited seawater. The interface between the spacer/detergent mix and the OBM will be contained and back loaded for onshore disposal. The inhibited seawater will be left in place until the well is brought into production when it will be flowed back to the FPSO on well start-up. During the course of operations, EnQuest will follow a hierarchy of choices when dealing with contaminated fluid in order to minimise the volume discharged to sea, in line with Oil and Gas UK "Good Practice for Clean-Up Operations" document (OGUK 2006). The well bore clean-up pill, plus any interface containing visible OBM generated during the clean-up will be shipped to shore for disposal. However, any wastewater containing no visible OBM will be discharged into the marine environment. This discharge will be permitted under Condition 5 of the PON15B approval. All discharges will be sampled, analysed and reported at the end of the drilling operation. Any residual oils in discharged water are likely to be rapidly dispersed in the water column and broken down through bio-physical weathering processes. If any sheen is

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observed on the sea surface during wellbore clean-up, this will be reported using a PON 1. There will be no flaring associated with the clean-up of the well.

5.2.1.6 Protection

Horizontal Xmas trees will be used for the well heads. They have a relatively low profile and allow the manufacturer to offer a protection structure integral with the tree frame and including deflection members. It is assumed that the trees will be provided with an integrated protection frame and that the conductor has been cemented such that it provides adequate resistance to fishing interaction loads. A conductor/riser analysis will be performed to confirm the wellhead is able to withstand the predicted snag loading from fishing activity in the area. The protection structure will be of a type approved by the Scottish Fishermen’s Federation (SFF). Such structures typically feature raked sides that are designed to lift trawl wires and gear up and over, significantly reducing the risk of snagging.

5.2.2 Well Footprint

5.2.2.1 Atmosphere

Exhaust gas emissions Estimated emissions from combustion of fuel are summarised in Table 5-2. Estimates for vessels are based on the maximum number of days deployed and the worst-case fuel use in that period. Table 5-2: Drilling exhaust gas emissions Vessel Types Total Fuel Total Emissions (tonnes) Duration Use (days) (tonnes) CO2 CO NOx N2O CH4 VOC SOx Drilling rig 92 1,104 3,533 8.83 65.14 0.24 2.98 2.65 2.21 Standby vessel 92 460 1,472 3.68 27.14 0.10 1.24 1.10 0.92 Supply boat 23 230 736 1.84 13.57 0.05 0.62 0.55 0.46 Anchor 4 handling 48 154 0.38 2.83 0.01 0.13 0.12 0.10 Helicopter 26 38 123 0.20 0.48 0.01 0.00 0.03 0.08 Total - 1,880 6,017 14.94 109.16 0.41 4.98 4.45 3.76 Source: Emissions factors taken from OGUK (2008) Airborne noise The potential airborne noise sources from drilling are summarised in Table 5-3.

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Table 5-3: Summary of drilling noise sources and activities Activity Source Frequency Duration Manoeuvring of semi- Propellers and bow and stern Continuous submersible rig thrusters Short-term (days, Deployment and adjustment of Winches and anchor chains Occasional weeks) anchors Transport (equipment and Helicopters and support vessels Regular Medium- personnel) term Drilling Machinery noise Continuous (months)

Airborne sound propagation is affected by the proximity of the sound source to the ground or sea level. Vertical propagation is influenced by reflections and wave transmissions across the surface and wind refraction and temperature gradients which produce poor sound transmission in the upwind direction and enhances sound transmission downwind. Although airborne noise is an important issue the main receptor affected are humans. The impacts on human health are best addressed through occupational health assessments, mitigation, and regulations and are outside the scope of this EIA.

5.2.2.2 Water resources

Chemical discharges The chemicals discharged during the drilling programme are relatively benign, the majority being risk assessed by the Centre for Environment, Fisheries and Aquaculture Sciences (CEFAS) as hazard quotient (HQ) colour band Gold or Offshore Chemical Notification Scheme (OCNS) category E. These are categories for products that present the lowest hazard to the environment. Furthermore, the majority of the category E chemicals have been classed by OSPAR as posing little or no risk (PLONOR) to the marine environment. A minority of chemicals will be discharged that have a higher HQ (i.e., a lower environmental profile) or that have been marked as candidates for substitution (SUB) as they contain components that have high toxicity, low biodegradation and/or potential for bioaccumulation. Chemical use will be minimised where operationally possible and all discharges risk-assessed via the PON15B process. A preliminary list of the chemicals to be used and discharged is supplied in Appendix C. Waste water discharge The drilling rig will discharge grey water (from washing and laundry facilities etc) and sewage. Table 5-4 gives an estimation of these discharges. Sewage discharge from the drilling rig undergoes some treatment prior to release. This can vary from fine screen maceration to full enzyme degradation. Discharges from supply and support vessels during the drilling campaign will undergo the level of treatment required by shipping regulations. The figures below assume all vessels will discharge grey water and sewage to sea (worst-case). In practice, most supply vessels will be on site for a limited period and it is more likely that they will retain any waste onboard and unload it in port.

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Table 5-4: Total waste water discharge (m3) during drilling Construction Vessels Duration1 Grey water2 Sewage2 Total waste Activity (days) (m3) (m3) water (m3) Drilling of well Drilling rig 92 1,380 644 2024 Standby vessel 92 166 77 243 Supply boats 26 117 55 172 Anchor handling tug 26 59 27 86 Total 236 1,721 803 2,524 1 Not all vessels will be present for entire duration of each activity. Figure given is combined maximum number of days vessel will be present on site 2 Estimates based on 150L of grey water per person per day and 70L of sewage/black water per person per day. Underwater noise The characteristics of underwater noise sources expected during drilling are shown in Table 5-5. Sound is attenuated as it propagates through the water. The local oceanographic conditions will affect both the path of the sound into the water column and how much sound is transmitted. Table 5-5: Summary of underwater noise produced during drilling activities Source Sound Pressure Levels (SPL) of underwater noise * (dB re 1 µPa @ 1m) (predominant frequency if known) Median Ambient Level 80 to 100 (1 - > 30,000 Hz) Drilling from rig 120 to 130 Anchor Tug 140 to 170 Supply / Support Vessel 160 to 170 (100 to 1,000Hz) Helicopters at various altitudes 101 to 109** * Most data taken from 1/3-octave band centre frequencies (50-2000Hz) ** Measured at the water surface Source: WDCS (2004), Richardson et al. (1995) The main receptors affected by underwater noise are fish and marine mammals and these impacts are discussed further in Section 8.

5.2.2.3 Seabed

Drilling rig When the rig anchors are lifted clear at the end of the operation, the anchor levers sediment onto the seabed. This creates either a mound, or an area of disturbed seabed. The size of the anchor mound is dependent on the seabed characteristics. Anchor mounds are common where seabed sediments or shallow sub-surface sediments are composed of clay. Section 7.1 illustrates that sediments within the Galia field comprise a thin layer of sand over sandy gravelly clay, which will be conducive to the creation of anchor mounds. Sidescan sonar images of the region (GGL 2011) clearly show disturbed areas of seabed, possibly associated with anchor pull out from previous drilling campaigns and more than likely from the Duncan field decommissioning. It is therefore likely that up to eight anchor mounds will be left on the seabed at the Galia drill centre during the proposed development. Each anchor will have an impact area of approximately 25m2 such that the total area of seabed impacted by all 8 anchor mounds is 200m2 (Table 5-16).

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The anchors will be attached to the drilling rig with a chain and cable combination. Approximately 300m of chain will be in contact with the seabed. This will provide additional anchoring hold, but will also create gouges and scar marks as the chains move under wind and tidal influence. Based on the assumption that the each anchor will create a 300m long, 1m wide scar it has been calculated that the scarring will affect 2,400m2 of seabed (Table 5-16). Safety exclusion zones A 500m safety exclusion zone will be established around the drilling rig for the duration of the drilling period i.e., approximately 92 days. This will exclude other vessels from 0.78km2 of sea.

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Figure 5-3: Field layout showing anchor patterns for Galia in relation to Alma development

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Drill cuttings Table 5-6 summarises the weight of cuttings (based on a preliminary well design) to be generated from the well and the fate of the cuttings. Exact section lengths and cuttings weights will be provided in the PON15B for the well. Table 5-6: Weight and discharge fate of drill cuttings (tonnes) Well Discharged to seabed Discharged 1m below Skipped and shipped sea level Galia 912 368 310

Cuttings pile Cuttings discharged directly on to the seabed will form a deposition pile around the wellhead. Studies of historical cuttings piles in the central and northern North Sea are available and in principle could be used to estimate the likely footprint. However these studies cannot be readily applied to a single well where WBM has been used. OSPAR Recommendation 2006/5 (Section 2.3) defines a cuttings pile as “an accumulation of cuttings on the seabed which has been derived from more than one well” – and single well developments were not included in the historical data reviewed. Furthermore, only examples dating from before 1st January 2001 and containing OBM were considered in these studies. These cuttings piles have experienced years of natural erosion and dispersion. It is also likely that the associated OBM would influence the cohesive properties of cutting differently to WBMs used today. For these reasons, it is not appropriate to use this methodology to assess the area of the deposition pile. Under conditions of low current speed it is assumed that this pile would form in the shape of a cone, with a slope angle of 18° (i.e., a height-to-radius ratio of 1:3; the cone will be six times wider than it is high). This assumption is based on the physical properties of sand. However, it is likely that bottom currents will rapidly re-suspend and mobilise the cuttings, spreading them over a larger area. Significant erosion of cuttings piles is thought to start when seabed current velocity reaches 0.35ms-1 based on studies at Beryl and Ekofisk (UKOOA, 2002). This is demonstrated in the southern North Sea, where cuttings have not accumulated around installations because strong currents and wave action have rapidly dispersed them (UKOOA, 2002). In addition, as the associated WBM dissolves, the cuttings will lose cohesion and spread out. With this in mind the extent of a cuttings pile, still assuming it will take the shape of a cone, has been calculated for a range of slope angles (see Figure 5- 4). Figure 5-4 illustrates that for a cuttings discharge of 442m3 (912 tonnes) the cuttings pile is likely to have a footprint on the seabed in the range of 374m² (if slope is 18°) to 2,627m² (if slope is 1°).

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Figure 5-4: Area of seabed covered by cuttings pile

3000

2500

2000 ) 2

1500 Area (m 1000

500

0 0° 2° 4° 6° 8° 10° 12° 14° 16° 18° 20° Slope Angle

Cuttings dispersion If WBM is used then cuttings from the 17½" section will be discharged 1m to 10m below the sea surface from the drilling rig. Cuttings will be dispersed over a wider area of seabed as currents transport them away from the discharge point. The pattern of drill cuttings deposition from the rig is expected to be similar to that experienced from other wells drilled in the CNS. Cuttings are deposited in an elliptical orientation along the major axis of current flow (generally northeast to southwest in the CNS). Deposition of cuttings over a thickness of 1mm is generally confined to within 500m of the discharge location (UKOOA 1999).

5.2.3 Flowline and Subsea Infrastructure project description

One flexible 8” production flowline will be installed in the Galia field to tie the well to the Alma production centre. A chemical umbilical and power cable will also be installed. The umbilical and the power cable will be trenched separately alongside the production flowline. All lines will be trenched and backfilled. The flowline, umbilical and power cable trenches will be 30m apart. A standby vessel will be on-site during the installation of the flowline. Dropped object protection (concrete mattresses) will be placed around the wellhead areas.

5.2.3.1 Flowline installation and commissioning

Installation of the flowline will follow the process below:

Trenched and backfilled

Flooded with chemically inhibited seawater

Tied-in at both ends, i.e. Galia tree and Alma production manifold

Hydrotested

Leak-tested

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Dewatered and commissioned A pipeline route survey has been completed. A visual survey with ROV will be conducted prior to pipelay. Further visual surveys will be undertaken as the flowline is laid as well as on completion of lay. The flowline, control umbilical and power cable will be laid using a dynamically positioned (DP) pipelay vessel. A DP vessel uses thrusters to position itself over the proposed route. A typical vessel used for this type of operation has a draft of 6.5m. The housing for the thruster propellers may extend to a maximum of 2m below this depth. The propellers create disturbance in the water column typically to 5m, below which the effects are not discernible from natural currents and wave orbital movements. Therefore, the deepest effects from a DP vessel are anticipated to reach down to approximately 14m from the sea surface. At the start of the installation process an initiation clump weight (typically a cubic metre of concrete with a tested eye on top to which the initiation head is attached to) will be used to initiate the lay. Touch-down of the flowlines will be monitored by a ROV. After the lay is complete the clump weight will be recovered to the deck of the vessel. The Galia field flowline, umbilical and power cable will be laid into separate pre- cut trenches into the seabed. The trenches will be cut utilising a Multi-Pass Plough (MPP), see Figure 5-5 below. The plough is attached to a winch on the vessel deck and is deployed to the seabed by an A-Frame mounted on the stern of the vessel. After lowering the MPP to the seabed the vessel will commence moving in DP mode in the direction of the planned trench route. The MPP will be towed along the seabed and the trench will start to cut with the depth and width of the trench controlled by hydraulic cylinder adjustments to control the attitude on the MPP. The trenches to be cut are typically to be 1.6- 1.8m deep and will be cut at approximately 250mhr-1 and will be trenched 30m apart. Figure 5-5: Typical Multi-Pass Plough

Spoil from the trench is positioned on either side in shallow berms (Figure 5-6). Trenches have been designed to be 5.2m wide at the top of the trench with berms up to 3m wide and 0.8m high, although it is anticipated that the mould

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boards will push them back and smooth off the slope. The berms are expected to be naturally removed through sediment movements within a short period. The footprint of the plough to be used at Galia will be a maximum of 13m wide (with mould boards out) over the length of the trench (5.3km). To allow for a worst case assessment, a maximum plough width of 20m has been used. Figure 5-6: Typical trench created by displacement plough

Trenching is expected to take up to 4 days to complete, allowing for any delays. The trenches will be initiated from the Galia tree and terminated at the Alma production manifold. The target depth for each of the trenches will be a maximum of 1.8m allowing for 0.6m cover from top of flowline to mean seabed level. The trench depth has been selected based on a consideration of the geotechnical characteristics of the area, the geotechnical site survey (GGL 2011) and from estimated upheaval buckling criteria. The trench depth selected has been designed to eliminate the need for rock dumping. The trenches will be allowed to naturally backfill. This will allow sediments to fill in the trench through normal seabed processes. Figure 5-7 below shows an indicative trench profile similar to the ones that will be seen at Galia. Please note that the units (not shown on figure) are millimetres. Figure 5-7: Indicative trench profile created by MMP plough

After backfill, the final seabed profile will be a shallow depression over the flowline due to the loss of finer sediments from displaced material through winnowing. Small residual berms may be present along the routes following backfill. Concrete mattresses will be used for protection on the approach to the Galia tree and the Alma production manifold. They consist of hexagonal concrete

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elements linked together with high strength non-degradable polypropylene rope. Mattresses are approximately 6m by 3m in dimension and 300mm thick. Approximately 25 mattresses will be used per trench at each end, with a total of 150 mattresses. Grout bags may be used at smaller exposed areas, typically at joins between mattresses and close by to the wellhead and production manifold. Commissioning Once installed, the production flowline will be filled and hydrotested using inhibited seawater pumped from a dive support vessel (DSV). The pipeline is pressurised (with inhibited seawater) and the test pressure held for 24 hours before the flowline is depressurised. The inhibited seawater is typically discharged from the DSV at the sea surface. After hydrotesting, the flowline will be tied-in at both ends and leak-tested. Leak testing follows a similar procedure to hydrotesting, using inhibited seawater. The additional quantities of inhibited seawater pumped into the flowline to establish leak test pressures will be discharged as above. Once fully installed and tested, the volume of inhibited seawater remaining in the production flowline will be flowed ahead of produced fluids to the FPSO where they will pass through the process system. Exact details of the chemicals to be used during flooding, hydrotesting and leak-test were not available at the time of the ES submission, but will be provided in the PON15C for the flowline as required under the Offshore Chemical (Amendment) Regulations 2011 and submitted to for approval to the DECC at least 28 days prior. The control umbilical and power cable will be installed in a similar manner to the production flowline, although there will be no chemicals used in the commissioning of the power cable. The control umbilical includes hydraulic, chemical and electric functionality. During installation, the hydraulic and chemical lines will be filled and pressurised to a relatively low pressure, typically 70 bar. The hydraulic lines will be filled with the control fluid Aqualink HT804 v2. The chemical lines will be filled with monoethylene glycol and potable water mix 80/20 by volume. During commissioning of the hydraulic lines, the valves connected to the control system will be actuated and a small amount of the control fluid will be discharged. For the chemical lines the water glycol mix will be injected into the flowlines and returned to the processing facilities on the FPSO. In total, three vessels will be used for installation and commissioning:

Trenching vessel

Pipeline installation vessel

Dive support vessel

Protection To provide cathodic corrosion protection, sacrificial anodes will be attached at regular intervals along the production flowline. The volume, composition and location of the anodes will be determined during detailed design.

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Anodes are an aluminium zinc indium alloy, typical specifications for which are given in Table 5-7. Anodes vary in weight and are designed to provide protection to the flowline for 10 years. Table 5-7: Sacrificial anode composition Chemical Composition (% by weight) Cadmium 0.002 (maximum) Copper 0.005 (maximum) Indium 0.016 - 0.030 Iron 0.09 (maximum) Silicon 0.10 (maximum) Zinc 4 - 6 Others (each) 0.02 (maximum) Aluminium Remainder

5.2.3.2 Production flowline and control umbilical tie-in

The production flowline will be tied in to the Galia well and the Alma production manifold using flexible jumpers and spool pieces. The jumpers and spool pieces will be pre-filled with monoethylene glycol (MEG), surface laid and connected at each end. Typically five dye sticks, such as Dyestick RX-9034A (which weigh 50g), will be placed in the spool pieces to assist with leak detection. Once the spool pieces are connected, they will be leak tested. MEG dyed with RX-9022, at a concentration of 100mgl-1 will be pumped into the spool pieces to increase the pressure in the line. Once test pressure is established the pressure will be released by discharging the fluids. The chemicals used during leak testing will be introduced and discharged from the DSV. The chemicals remaining in the flowline and spool pieces after the leak test at commissioning will remain in the flowline until the well comes on to production. They will then be exported to the FPSO with produced oil where they will enter the production train and eventually be re-injected with produced water, or discharged overboard if the produced water re-injection is not online. The chemical cores in the new sections of control umbilical will be pre-filled onshore with the field’s control fluid; Castrol Transaqua HT2 or an equivalent control fluid. On start-up of the production well it will be pushed out of the chemical cores and into the production flowline, from where it will be produced back to the FPSO with first oil.

5.2.4 Flowline and subsea infrastructure footprint

5.2.4.1 Atmospheric emissions

Estimates for the atmospheric emissions from each of the support vessels are summarised in Table 5-8. Estimates for vessels are based on the maximum number of days vessels will be on-site and the worst-case fuel use in that period.

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Table 5-8: Flowline installation exhaust gas emissions Vessel Types Duration Total Fuel Total Emissions (tonnes) (days) Use (tonnes) CO2 CO NOx N2O CH4 VOC SOx Flowline 4 installation vessel 40 128 0.32 2.36 0.01 0.11 0.10 0.08 Trenching vessel 4 20 64 0.16 1.18 0.00 0.05 0.05 0.04 Diving support 7 vessel 70 224 0.56 4.13 0.02 0.19 0.17 0.14 Total 15 130 416 1.04 7.67 0.03 0.35 0.31 0.26 Source: Emissions factors taken from OGUK (2008) 5.2.4.2 Water resources

Chemical discharge Chemicals could potentially be discharged to sea during various stages in the flowline installation and commissioning and the well tie-in. Examples of the types and quantities of chemicals to be used are provided in Appendix C. These are subject to change and exact details will be provided in the PON15C as required under the Offshore Chemical (Amendment) Regulations 2011. Waste water discharge It is possible that during installation of the flowline the installation and support vessels will discharge grey water (from washing and laundry facilities etc) and sewage. Table 5-9 gives an estimation of these discharges. Discharges from construction vessels will undergo the level of treatment required by shipping regulations. The estimations provided assume all construction vessels will discharge grey water and sewage to sea (worst-case). In practice, most construction vessels will be on site for a limited period and it is more likely that they will retain any waste onboard and unload it in port. Table 5-9: Total waste water discharge during installation and tie-in Construction Vessels Duration Grey Sewage1 Total waste Activity (days) water1 (m3) (m3) water (m3) Flowline Flowline installation vessel 4 146 68 214 installation Trenching vessel 4 146 68 214 Diver support vessel 7 98 46 143 Total - 327 389 182 571 1 Estimates based on 150 litres of grey water per person per day and 70 litres of sewage/black water per person per day. Underwater noise Noise from flowline installation is not anticipated to be significant above normal background noise.

5.2.4.3 Seabed

Installation Table 5-10 summarises the footprint on the seabed as a result of the flowline installation and production well tie-in.

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Table 5-10: Summary of installation footprint on the seabed Activity Comments Length Width Number Footprint on (m) (m) seabed (m2) Flowline initiation Initiation clump weight 1 1 1 1 Trenching Flowline 5,300 20 1 106,000 Umbilical 5,300 20 1 106,000 Power cable 5,300 20 1 106,000 Concrete - 6 3 150 2,700 mattressing Well Head - 9 9 1 81 Total - - - - 320,782

Safety exclusion zones There is no formal safety exclusion zone around the installation of the subsea infrastructure. However, fishing vessels will be asked to keep 500m away from the trenches on either side during installation. Notification will be issued via Kingfisher. EnQuest has requested approximately 70 days to allow for operational contingency.

5.3 PRODUCTION

As the Galia well will be tied back to the Alma production centre and produced via the EnQuest Producer FPSO, this section discusses the incremental effect Galia will have on the current production forecasts for the FPSO as detailed in the Alma ES (DECC Reference D/4110/2011).

5.3.1.1 Host Facilities – EnQuest Producer FPSO

The EnQuest Producer (Figure 5-8) entered operation in 1995 at the Flora and Fife field (including Angus and Fergus fields) for Amerada Hess under the name of Uisge Gorm. The FPSO will be upgraded as part of the overall Alma/Galia development. Modifications and upgrades will be carried out on the FPSO turret to accommodate the new flowline/umbilical riser systems required to receive and process the Alma and Galia hydrocarbons and to pump injection water. The upgrades will be finished before the FPSO is mobilised to the field.

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Figure 5-8: EnQuest Producer FPSO

Source: www.bluewater-offshore.com The FPSO will support all production activities with crude oil offloading every two weeks.

5.3.2 Increase in Production

Table 5-11 below shows the current estimates for production from both the Galia and Alma fields. Table 5-11: Production estimates for Galia and Alma Galia Alma Oil Gas Oil Gas Tonnes m3(x106) Tonnes (x106) m3 (x106) (x106) Low recovery case 0.88 78.1 2.27 121.1 Base recovery case 1.15 101.6 3.02 161.3 High recovery case 1.42 126.0 4.3 229.5

If both developments produce at base recovery levels, the addition of Galia will result in a 38% increase for oil and a 63% increase for gas. However, if Galia was to produce at the high recovery level (and Alma at base case) then this would result in a 47% increase for oil and a 7% increase for gas. For the base case the Galia production represents 28% of the total oil production through the FPSO, and 39% of the gas. The emissions associated with increased power generation (and flaring are addressed in Section 5.3.6.

5.3.3 Chemical Use

The tie-back of Galia to the FPSO will require an increase to the chemical requirements during production. The main chemicals affected will be control fluids and inhibitors.

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Chemicals will be supplied to the well through the chemical umbilical. In general terms the increase in inhibition chemical usage will be similar to the Galia production increase in Section 5.3.2. A water-based subsea hydraulic control fluid will be supplied through the control umbilicals from the FPSO to the control wellhead valves on the Xmas tree. The system operates as an open-loop system (industry standard). This means that small amounts of control fluid are discharged near the seabed from the directional control valves when they are opened and closed. The typical discharge from the wellhead will be a total of 3m3 to sea per year. All chemical use will be permitted under an Offshore Chemical (Amendment) Regulations 2011 chemical permit i.e., PON15D. The majority of chemicals will be within a closed system with no discharge to sea; however some chemicals such as control fluids may be discharged at the wellheads. These permitted discharges will be risk assessed.

5.3.4 Produced Water

At the start of field life the Galia well is expected to flow dry for the first few months. It will then increase steadily rising to 75% after 3 years, with an average water cut of 35%. As the reservoir declines the water cut will increase and by the end of field life the oil water ratio will be 95% water and 5% oil (5bbls of oil for every 95bbls of water). Under normal operations all produced water (PW) from the Galia well will co- mingled with the produced water from Alma and will be re-injected with treated seawater into the Alma water injection wells. The PW system on board the FPSO has been designed to handle up to 140,000bwpd (22,260m3d-1). Production forecasts suggest that the Galia field will produce a maximum of 8,210bwpd (1,305m3d-1) of water per day (EnQuest 2011a), which when combined with the maximum produced water from Alma (120,000bwpd; 19,080m3d-1) is still within system capacity. PW may also be discharged to sea in the event that production (from all wells) starts prior to the commissioning of the injection wells. This scenario is thought to have a low likelihood of occurrence due to the scheduled yard works and planned deliveries for the major FPSO engineering rolling into Q1 2013. The subsequent installation onto the vessel, onshore commissioning and transit to field for hook up, are activities which are difficult to accelerate by any appreciable amount, therefore the chance of acceleration of topsides is low. A number of factors will determine the start of the WI well drilling; during Q2/Q3 2013 drilling operations at the production drill centre will have to cease to allow installation and tie-in operations for the subsea equipment, therefore EnQuest may choose to finish production drilling early, to move to the WI drill centre to provide access for tie-ins, therefore the start of the water injection drilling is not necessarily tied to completion risk for all of the production wells. In addition drilling times are based on P50 estimates, it is expected that these can be improved upon. In the unlikely event that the scenario materialises, under normal operating conditions produced water (from both Alma and Galia) will be discharged at a maximum OIW content of 30mgl-1. It is expected that the maximum quantity of PW discharged will be 1,521m3day-1 (9564bblday-1) over a period of up to six months (i.e. 182 days). During this period up to 8.3 tonnes of oil may be

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discharged at a rate of up to 45.6kgday-1. However all efforts will be directed to minimise the time that PW is discharged. The PW plant comprises 3-off hydrocyclone vessels (which provide flexibility for maintenance), and 2-off degasser vessels and polisher vessel with a return of the oil to the main separation plant. Produced water will, in normal operation, be completely reinjected. During periodic maintenance or equipment downtime; produced water may be discharged to sea. The PW system has been designed to achieve, as a minimum, oil in water (OIW) concentrations of 30mgl-1. Historically, the EnQuest Producer (as the Uisge Gorm) was regularly achieving OIW concentrations of <15mgl-1 on the Flora and Fife fields (including Angus and Fergus). EnQuest are committed to a performance standard of <30mgl-1 for all PW injected so that if the system trips there is the option to discharge PW overboard.

5.3.5 Sewage Treatment and Drainage

The tie-back of Galia to the FPSO will not change the sewage treatment or drainage requirements or quantities that are in place for the Alma Field. As the EnQuest Producer does not have a sewage treatment plant, all sewage and food waste is macerated before being discharged overboard. No practical method of updating the system that delivers a substantially better environmental performance has been found to date. All fluids entering the drain system are routed to the slops treatment system, processed through the produced water system and re-injected with the produced water.

5.3.6 Production Footprint

5.3.6.1 Atmosphere

Power Generation The incremental emissions associated with Galia production have three components, as follows:

Additional emissions associated with the power required to drive the Galia ESP(s),

A proportion of the ‘overhead’ power requirements at the FPSO

A reduction in emissions associated with the Galia produced gas being available to replace use of Alma crude as a fuel Compared to the Alma field, the Galia reservoir is relatively high energy. It does not require water injection, ESP power requirements are lower and there is a high GOR. The net effect is that the above there factors balance out such that atmospheric emissions from power generation over the field life will not significantly increase as a result of Galia. Flaring Produced gas will normally be used for power generation such that it is expected that gas will only be flared in an emergency situation, under abnormal operations and when excess gas is produced in early years. The field

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development plan indicates that for the High Case, flaring over the field life is estimated to be 93.5 million Sm3 (2,120 mmscf). The peak year for flaring is 2014, during which 60.0 million Sm3 of gas would be flared under the high case. The corresponding quantities of CO2 emitted for the High production case are 268,000 tonnes and 172,000 tonnes respectively. For the Base Case, the quantities flared are approximately 53% of the High Case. The maximum worst case rate of flaring at the FPSO will occur for a short period early in field life and is estimated to be 198,000 Sm3d-1 (7 mmscfd-1). The rate is for both Galia and Alma combined and Table 5-12 provides an emission breakdown for this maximum rate using the default emission factors in the Environmental Emissions Monitoring Scheme. Table 5-12: Flaring gas emissions during production Emission Emission Factor Gas Gas Emissions (tonne emission/ tonne gas (tonnes) / day burned)

CO2 2.8 568 CO 0.0067 1.36 NOx 0.0012 0.24

SO2 0.0000128 0.003

CH4 0.045 9 VOC 0.005 1.01

Emissions from vessels The number of vessels visiting the FPSO during production will not change either as a result of the Galia tie-back. Noise emissions There will be no significant change in the noise levels during production as a result of the Galia tie-back.

5.3.6.2 Water resources

All chemicals used for well maintenance will be in a closed system (supplied via umbilical) and produced back to the FPSO where they will either be reinjected with the PW or partition to the oil. Under normal operations, all PW will be re- injected into the water injection wells to ensure reservoir pressure at Alma is maintained. The tie-back of Galia is not expected to increase the frequency of outage of the PW system. However, if the PW pumps should fail then the Galia and Alma PW will be discharged together. The impact of this is discussed further in Section 7.3.5.2. The Galia tie-back will not have any impact on the amount of drainage or waste water discharged from the FPSO and visiting vessels during production.

5.3.6.3 Seabed conditions

A permanent 500m safety exclusion zone will be established around the well head. This will exclude vessels from 0.78km2 of sea for the duration of field life. No additional seabed disturbance is anticipated during production activities.

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5.4 DECOMMISSIONING

Field life is estimated to be ten years and therefore abandonment will occur around 2023. The arrangements for decommissioning of the subsea facilities and flowlines have been developed in accordance with the current UK Government legislation and international agreements in force. The decommissioning plan is based on the following assumptions:

Plug and abandon well

Removal of the conductor to below the mud line

Removal of the subsea xmas trees

Removal of the manifold

De-oil and remove the production flowline

Remove the power cable and control umbilical

Third party confirmation of seabed clearance Galia will be flushed from either the FPSO downhole until an acceptable level of cleanliness is achieved (match OIW limits) or from the Alma production manifold to Galia from a DSV (less favourable as it involves divers). However it should be noted that the water cut of the Galia well will be such that the well will no longer be viable at the time of decommissioning. The system will have had hot water with very little hydrocarbons running through for a time and should be relatively clean as a result.

5.5 PROJECT ACTIVITY SUMMARY

In conclusion, certain aspects of the project activities described in the above sections have the potential to interact with the environment. These project aspects are detailed in Table 5-13 below. If not scoped out below, their interaction with each environmental receptor has been assessed in Sections 7 to 9.

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Table 5-13: Summary of project activities and aspects Project Activity Project Aspects Construction Safety exclusion zones Anchoring Exhaust gas emissions Physical presence and Discharge of sewage, grey water, food waste and drainage movement of vessels water Subsea noise Physical presence and movement of vessels Increased vessel activity in region Bulk storage and transfer Dust release during transfer Subsea noise Discharge of cuttings Drilling of wells Discharge of chemicals (including WBM) Discharge of reservoir hydrocarbons Subsea noise Physical presence of subsea infrastructure and flowlines Installation of flowlines Trenching and backfill Discharge of chemicals Concrete mattressing and rock placement Production Exhaust gas emissions from power generation and gas flaring Operation and maintenance of Discharge of produced water FPSO Discharge of chemicals Safety exclusion zones Increased movement of export Exhaust gas emissions tanker and supply vessels Increased vessel activity in region Presence of flowlines Presence of subsea infrastructure and flowlines Accidental Events Overboard loss of equipment or Dropped objects waste Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon release Diesel, crude or chemical spill (including OBMs) (1-10 tonnes) Chemical / hydrocarbon release (>10 tonnes)

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5.5.1 Emissions to air

Table 5-14 below provides a summary of all emissions to air during both construction and production. Table 5-14: Summary of emissions to air from construction and production activities Activity Total Emissions (tonnes)

CO2 CO NOx N2O CH4 VOC SOx Construction Drilling exhaust gas emissions 6,017 14.94 109.16 0.41 4.98 4.45 3.76 (92 days) Flowlines installation exhaust 416 1.04 7.67 0.03 0.35 0.31 0.26 gas emissions (7 days) Production Flaring gas emissions 268,000 641 115 - 4,306 478 1.22 (10 years, High Case) Total emissions to air 274,433 657 232 0.44 4,311 483 5.2

Approximately 274,000 tonnes of CO2 will be emitted during construction and production. In 2010 the UK emissions from upstream oil and gas activities was approximately 9.6 million tonnes of CO2. (Source: 2010 UK Greenhouse Gas Emissions, DECC, 7th February 2012). If UK emission continued at this rate over the 10 year field life, the Galia (High Case) emissions would represent 0.3% - a relatively small contributor to annual UK emissions and not untypical for a standard oil development of this size. The main emissions with potential to contribute to deterioration in air quality are NOx and SOx. The respective emissions (Table 5-14) show the maximum daily emissions. The construction value assume that the flowline installation is in parallel with drilling, and the production values based on the maximum daily flaring for the high production case.

Emissions of SOx and NOx are known contributors to degradation of regional and local air quality. The European Commission has set threshold/limit values for NOx and SOx concentrations in ambient air to improve the protection of human health and the environment. For NOx the alert threshold is 500 parts -3 -3 per billion (ppb) (400μgm ) and for SOx the alert threshold is 30 ppb (80μgm ) if smoke concentrations are greater than 34μgm-3 (Dore et al. 2008). These thresholds are most likely to be exceeded in urban areas which combine large combustion sources and potential for stable air conditions. The Galia development is 280km east of the nearest landfall on the UK coastline. Given both the small contribution to overall UK atmospheric emissions and the distance of the installation from receptors with potential to be sensitive to air quality this aspect of the development has been scoped out from further assessment in Sections 7 to 9.

5.5.2 Emissions to water

Table 5-15 below provides a summary of all waste water discharge during construction.

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Table 5-15: Total waste water discharge during construction Construction Activity Grey water (m3) Sewage (m3) Total waste water (m3) Drilling well 1,721 803 2,524 Flowline installation 389 182 571 Total 2,110 985 3,095

As under normal operating conditions, there will be no increase in the waste water discharged during production from the FPSO as a result of the Galia tie- back, this has not been considered here. All chemical discharges during both construction and production will be risk assessed as part of the appropriate PON15 application and therefore have not been considered here in further detail. Appendix C provides a summary of expected chemical use and discharge and full chemical requirements will be confirmed in the relevant PON15B or PON15C chemical permit application to be submitted to the DECC at least 28 days before operations start. Chemicals to be used on the FPSO had not been confirmed at the time of ES submission but will be included in a PON15D chemical permit. Given the prevalent metocean conditions in the project area (e.g., winds, waves, tides and currents), the short-time scale of the construction period and the small cumulative volume of discharges, the marine environment will be able to rapidly assimilate the discharges through natural bacterial action. Any degradation in water quality will be transient (limited to a few hours after the discharge) therefore there are unlikely to be any significant impacts on any environmental receptor and consequently have been scoped out from further assessment in Sections 7 to 9. However as PW may be discharged to the marine environment for up to six months (in addition to those times discharge occurs as a result of a system trip), production impacts are not being scoped out.

5.5.3 Seabed Footprint

Table 5-16 below provides a summary of the seabed footprint of the Galia development.

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Table 5-16: Summary of seabed footprint - field development Aspect Length Width (m) Height / Number Footprint (m) depth (m) on seabed (m2) Drilling rig anchor mounds and chain 300 - - 8 2,400 scars Drilling rig anchor scars - - - 8 200 Well Head 9 9 6 1 81 Drill cuttings pile - 2,627 - 1 2,627 Flowline initiation clump weight 1 1 - 1 1 Trenching Flowline 5,300 20 1.8 1 106,000 Umbilical 5,300 20 1.8 1 106,000 Power cable 5,300 20 1.8 1 106,000 Concrete mattresses 6 3 - 150 2,700 Total 326,009

The tie-back of the Galia well will not have any impact on the footprint of the FPSO and therefore this has not been considered here. Further assessment of the impacts of the seabed footprint on appropriate environmental receptors has been carried out in Sections 7 to 9.

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6 ACCIDENTAL EVENTS

Accidental events are incidents or non-routine events that have the potential to trigger impacts that would otherwise not be anticipated during the normal course of construction, operation or decommissioning. The severity of impact from accidental events can be greater than those from routine operations, however the probability of an accidental event occurring is typically much lower. Given the high potential severity of accidental events, they require plans specifically designed to respond to the event as quickly and effectively as possible. In addition to mobilising the operator’s resources, additional resources from external parties such as government agencies are often an inherent part of the incident response. EnQuest will submit an addendum to the Alma drilling oil pollution emergency plan (OPEP) to the DECC Offshore Inspectorate for approval to cover the drilling activities at the Galia Field. A separate field OPEP will be submitted to the DECC to cover the operational phase of the combined Alma and Galia developments. The OPEPs will comply with the requirements of The Offshore Installations (Emergency Pollution Control) Regulations 2002 and The Merchant Shipping (Oil Pollution Preparedness, Response Cooperation Convention) Regulations 1998 and take into consideration recent revised guidance from the DECC following the Gulf of Mexico Macondo incident. For the purpose of this assessment, the following accidental events have been considered:

Hydrocarbon spills / leaks

Chemical spills / leaks

Dropped objects Accidental releases of produced hydrocarbons from identified potential worst case spill scenarios have been assessed and modelling studies carried out to characterise the extent of the impact. These results are presented in Section 6.4 and Appendix B.

6.1 TYPES OF ACCIDENTAL EVENT

6.1.1 Hydrocarbon Spills and Leaks

The characteristics of liquid hydrocarbons used and produced during the project phases are summarised below. These include diesel, lubricating and hydraulic oils, crude oil and aviation fuel. Spills and leaks of gas and condensate have not been considered below because both liquids are non-toxic and, as they vaporise quickly, they will have a minimal impact on the marine environment in the unlikely event of a spill. All spills and leaks of hydrocarbons will be reported to the DECC via PON1 notification system. Crude Oil There is a small chance that a crude oil spill could occur in association with the Galia development due to:

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A collision causing loss of inventory from the FPSO and/or the export tanker (modelled as part of the Alma ES)

Loss of inventory from the export flowline due to a rupture or incident such as fishing damage

Loss of well control (blow out) Accidental releases of produced hydrocarbons from identified potential sources have been assessed and modelling of the relevant scenarios carried out to characterise the extent of the impact (see Section 6.4). The most recent UK guidance on oil pollution emergency response requires Operators to model a loss of well control (blow out), as this although an extremely rare occurrence in the UK is considered to be the worst case volume of crude oil that could be spilt from a development. The maximum flow rate for the Galia well would be 1,992 tonnes (2,385m3) of crude oil per day. The modelling results are presented in Section 6.4 and Appendix B. The scenario modelled for the Alma ES was if the FPSO and export tanker collided resulting in the total loss of inventory from both vessels. Neither vessel would be full to capacity at the same time in the same location, so as the export tanker has the largest capacity (87,000 tonnes, 100,000m3) this was the total amount modelled. The Galia crude has an API of about 38° and modelling shows that it is likely to emulsify, with an expected water content of 80%. Diesel Marine diesel used in mobile drilling rigs and support vessels is a low viscosity distillate fuel. Diesel contains a high proportion of lighter hydrocarbons, such that evaporation is an important process contributing to the removal of spilt diesel from the sea surface. Evaporation will be enhanced by higher wind speeds and warmer sea and air temperatures. The general behaviour of diesel at sea can be summarised as follows:

A slick of diesel will elongate rapidly in the direction of the prevailing wind and waves.

Very rapid spreading of the low viscosity diesel will take place.

Some diesel fuel oils may form an unstable emulsion at the thicker, leading edges of the slick.

Speed of physical dispersion of the surface slick increases with wind speed. Up to 95 % of a slick may disperse within about 4 hours of the spill in 15 knot winds and sea conditions. Only the worst case spill scenarios for the greatest inventory of diesel offshore for the development have been modelled. This would be from the FPSO and export tanker colliding into each other during offloading. The combined inventory of the two vessels has been modelled and the results are shown in Section 6.4. Lubricating and Hydraulic Oil Lubricating oils behave in a manner similar to marine diesel but are more viscous, slowing down the spread of the slick marginally. As lubricating oils are considerably refined, they do not contain the same quantity or ratio of light-end

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hydrocarbons. Hydraulic oils are medium oils of light to moderate viscosity. They have a rapid spreading rate and generally dissipate quickly, particularly in higher sea states. Lubricating and hydraulic oils are used in a variety of equipment on both drilling rigs and support vessels and are stored in containers ranging from 20 to 1,000L. Aviation Fuel Aviation fuel is volatile and evaporates and spreads quickly. Since the fuel will mostly evaporate, leaving little or no visible mass left on the surface within 24 hours, it is unlikely there would be sufficient time for clean-up operations in the event of a spill. Aviation fuel is used for refuelling helicopters that will transport equipment and personnel to and from the drilling rig and other offshore vessels to shore.

6.1.2 Chemical Spills and Leaks

During the life of the project there is the potential for chemical spills and leaks to occur. Spills may result in localised impacts on water quality and toxicity effects on marine fauna and flora. Chemical spills include accidental leakage of hydraulic fluid or chemical inhibitors used in the wells or accidental release of chemicals during transfer between vessels. All chemicals used during construction and production will be permitted under the Offshore Chemical (Amendment) Regulations 2011 (OCR). Chemicals that are to be discharged undergo a risk assessment. A comprehensive list of chemicals will be developed during the detailed engineering phase of the project. Bulk chemicals stored during the commissioning and operational phase of the project that are considered in this section are:

Chemicals used during the drilling of the wells (PON15B) e.g. oil and water based drilling muds, cement chemicals, completion chemicals, rig wash, hydraulics fluids etc

Chemicals used during the installation and commissioning of the flowline and control umbilical (PON15C) e.g. methanol or MEG, corrosion inhibitor, dyes etc

Chemicals used during production (PON15D) e.g., wax inhibitor, asphaltene / demulsifier, scale inhibitor, methanol or MEG, corrosion inhibitor etc Specific effects on individual receptors would depend upon the type and volume of chemical released but is broadly similar to the receptors discussed in relation to hydrocarbon spills. All chemical spills and leaks will be reported to the DECC via PON1 notification system

6.1.3 Dropped Objects

Dropped objects or loss of items to sea have the potential to increase the project footprint on the seabed (or damage subsea infrastructure) if the objects are not recovered. Such items can also present a hazard up until the point at which they have been recovered. They also pose a risk to other sea users as snagging hazards, can get caught in propellers or are a collision risk. Occurrences of dropped objects are most likely during drilling activities and during vessel transfer operations or adverse weather conditions.

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Subsea equipment associated with the Galia development will be subject to dropped object studies to ensure that the potential risks posed by dropped objects are reduced. All dropped objects or items lost to sea will be reported to the DECC on a PON2 form within 6 hours.

6.2 PROBABILITY OF ACCIDENTAL EVENTS OCCURRING

Typically the likelihood of accidental events occurring is minimised through legislation governing the industry, emergency shut-down procedures and multiple control and mitigation measures consistent with industry best practice across the project life cycle. Nevertheless, events are possible during both the construction and production phase. The most frequently expected type of spill would be a small (<1 tonne) spill of oil or chemical from the rig or FPSO during bulk transfer to/from the facilities, leakage or during use or storage. Four possible incidents have been identified within the project scope as potential sources for a major spill of hydrocarbons (>100 tonnes). These are considered to be the worst case scenarios possible:

Loss of diesel inventory from the FPSO and tanker through collision – 2,016 tonnes (2,400m3) from the FPSO and 2,881 tonnes (3,430m3) from the export tanker

Loss of crude oil inventory from the FPSO and tanker through collision – A maximum of 81,0901 tonnes (94,500m3) from the FPSO and a maximum of 87,000 tonnes (100,000m3) from the export tanker (note: neither vessel will be full at the same time) 3 Loss of well control (blow out) - 29,873 tonnes (35,775m ) over 15 days 3 Loss of diesel inventory from the drilling rig – 1,399 tonnes (1,665m ) The probability of an extensive release of hydrocarbons occurring on this project, during construction and/or production, has been assessed below.

6.2.1 Construction and drilling

Historical spill data in the UK is collated by both the DECC and the Maritime and Coastguard Agency (MCA). The DECC collates incident reports from offshore oil and gas installations, including drilling rigs, whereas the MCA collates incident reports from UK vessels, including those associated with support and construction activities for the oil and gas industry. The MCA data also incorporates data reported to the DECC to provide an overview of all marine incidents. Both sets of data have been used in the analysis below during the 3 month Galia construction period, during which the following vessel activity is envisaged:

Drilling rig – 92 days

Standby vessel to support rig – 92 days

Anchor handling vessel – 4 days

Vessels for flowline installation – combined total of 15 days on site

21 visits by supply vessels over 3 months

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The spill risk associated with these activities can be divided into two main categories: a) Offshore support vessels (e.g., standby, construction and supply vessels) b) Drilling rig Available data from the MCA (ACOPS reports) has been reviewed for years 2000 to 2009 (ACOPS 2001-2010) to establish the probability of a spill occurring from an offshore support vessel (category a) above). However, there are only two reported incidents which suggests, there is either little reported data for construction related incidents or the percentage of incidents is very low. Given the lack of data, an estimation of the likelihood of a spill from a support vessel occurring per annum would not be statistically valid. Historic data held by the DECC are more descriptive and can be used to establish the probability of a spill during drilling operations (category (b) above). Records for spills from mobile drilling units have been analysed for the period 2003 to 2007. Excluding very small spills (<0.1 tonnes), data for this period shows there were 32 spills from drilling rigs. Of these, 26 were less than 1 tonne and one was over 10 tonnes (13.4 tonnes oil based mud in 2006). Over the same period it is estimated that there were approximately 1,100 wells drilled from mobile drilling units such that the probability of a release of less than 1 tonne is approximately 2.5% per well and the probability of a release between 1 and 10 tonnes is 0.5% per well. There is not enough data for the larger spills (>10 tonnes) to estimate the likelihood of such a spill statistically although it can be inferred from the data that such spills are very rare. At Galia there will be one well drilled which gives a 2.5% likelihood of a release of less than 1 tonne and a 0.5% likelihood of a release of between 1 and 10 tonnes.

6.2.2 Production

During the project life cycle there is the potential for a loss of containment integrity of the oil production flowline leading to a release of approximately 267m3 of crude oil. The report “Riser and pipeline release frequencies” by the OGP (2010) states that failures in a pipeline may occur as a result of:

Loads exceeding pipeline critical loads, usually resulting in an isolated incident

Gradual weakening of the pipeline over a period of time. The primary causes of pipeline failures are critical loads that may lead to an isolated incident including loads from trawl boards, ship anchors or subsea landslide. The second cause of pipeline failures are mechanisms which act over time including corrosion, open spans causing fatigue and buckling (OGP 2010). Table 6-1 provides the recommended pipeline failure frequencies for the UK offshore oil and gas industry based on the above potential causes. Using this table it has been calculated that the annual probability of the production flowline failing in open sea is 0.0265% per year, the probability of it failing as a result of external damage is 0.079% per year and the probability of the risers failing is 0.36% per year. The combined likelihood is therefore approximately 0.34% per year or 3.44% over field life.

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Table 6-1: Industry riser and pipelines failure frequencies Failure Pipeline Category Unit frequency Subsea pipeline: in Well stream pipeline and other Per open sea small pipelines containing 5.0 x 10-4 km/year unprocessed fluid Processed oil or gas, pipeline Per 5.1 x 10-5 diameter ≤24 inch km/year Subsea pipeline: external loads Diameter ≤16 inch 7.9 x 10-4 Per year causing damage in safety zone Flexible pipelines: Per All 2.3 x 10-3 subsea km/year Steel – diameter ≤16 inch 9.1 x 10-4 Per year Risers Flexible 6.0 x 10-3 Per year Source: OGP (2010)

6.2.3 Summary

The probability of a spill occurring during construction is therefore approximately 3% for a spill of 0.1 to 1 tonne and less than 0.1% for a spill greater than 1 tonne. The probability of a spill occurring from the subsea infrastructure at Galia is approximately 3.4% over field life.

6.3 MANAGEMENT AND MITIGATION FOR HYDROCARBON SPILLS

EnQuest considers three levels of mitigation for hydrocarbon spills: Prevention In light of the significant consequences of a major accidental discharge, all operational personnel, whether in the direct employ of EnQuest or contractors will be made aware of existing environmental protection procedures and the crucial importance of maintaining the integrity of the containment policy. The risk of a spill is mitigated on a daily basis by EnQuest employees and contractors following good practice codes, collision avoidance and fuel handling and transfer procedures. Every effort will be made to prevent such spills. It is noted that most spills occur during offshore fuel transfer operations (bunkering) and as such EnQuest are committed to the following measures:

Fuel will be transferred between the vessels via hoses that will be equipped with a one way valve.

Bunkering operations will be conducted during day light hours and in good weather, where possible. If during winter this is not possible, transfers will be assessed to identify potential risks and any risks mitigated to acceptable levels.

A continuous watch will be maintained during offloading

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All bunkering operations will be conducted in strict compliance to contractor’s procedures. These procedures will be referenced in a combined EnQuest HSE Management System Bridging Document, which will be circulated to all appropriate personnel.

The management of bunkering operations will be discussed with the contractor’s team prior to commencement of operations. Control During the construction phase, the contractors owning each of the various construction vessels deployed will retain individual responsibility for spills and maintain approved shipboard oil pollution emergency plans (SOPEP). The addendum to the Alma drilling oil pollution emergency plan (OPEP) to cover the drilling activities at the Galia Field will be developed in line with the Merchant Shipping (Oil Pollution Preparedness and Response Convention) Regulations 1998, the UK Energy Research Centre and the latest DECC guidance on OPEP requirements following the Gulf of Mexico spill. The response to hydrocarbon release during the drilling and production phases will be outlined in an OPEP and referenced in a combined EnQuest HSE Management System Bridging Document, which will be circulated to all appropriate personnel. The OPEP will provide detailed hydrocarbon release and spill scenarios to enable the determination of appropriate offshore actions, and reporting and training requirements for mitigating accidental spillage throughout all phases of the development. The OPEPs will provide further detail on this assessment and, in addition, will include:

Definition of the response actions, including the roles and responsibilities of offshore and onshore personnel.

Reporting requirements of incidents, both internally amongst the offshore team (including contractors), and externally to statutory bodies such as the DECC, Her Majesty’s Coast Guard (HMCG) and the JNCC.

Model-based methodologies for determining the volume and potential movement of a slick based on the modelling. The scenarios identified for modelling as discussed below. EnQuest is also a member of OSPRAG which will provide support in the event of a major spill occurring. Remediation Any spills (crude oil, diesel or chemical), including sheens, will be reported to the statutory authorities using the PON1 system. For larger spills, a comprehensive range of back-up resources is available to EnQuest through oil spill providers. This includes trained staff, aerial surveillance and dispersant spraying capabilities. The EnQuest strategy for diesel spills in this region is to allow natural dispersion and to monitor the progress of this dispersion. In the unlikely event that a large crude spill occurred advice would be sought from the DECC, the Defra and the JNCC as to whether dispersant spraying would be appropriate and would be approved. Pipeline Failure

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The risks of pipeline failure will be managed through a combination of measures which include:

The selection of materials and design of the pipelines is far in excess of the known operating pressures and temperature.

A Major Accident Prevention Document evaluating the risks of pipeline failure

A written verification programme

Inspection repair and maintenance strategy in place and followed.

Post installation survey to ensure no installation damage has occurred and lay is as intended

Establishment of 500m safety zones around the FPSO and production and injector drill centres

Pipeline protection strategy

Marine procedures

Crude offloading procedures

Use of ERRV for patrolling duties If failure does occur a Pipeline Emergency Response Plan and OPEP will be in place in conjunction with a fully manned Emergency Response Centre with trained and competent personnel to manage any event

6.4 OIL SPILL MODELLING

6.4.1 Construction

As discussed above, during the construction phase there is the potential for loss of containment from the drilling rig leading to a release of diesel and fuel oil. If this were to happen, a maximum of 1,665m3 (1,399 tonnes) of diesel would be released instantaneously. This release is smaller than those for production. Modelling has only been undertaken for the worst case spill scenarios, which occur during production and are presented in Section 6.4.2 below. The drilling rig will not be on location at the same time as the export tanker and FPSO and therefore the three inventories could not combine in an incident. A loss of well control (blow out) would result in a spill of 1,992 tonnes (2,385m3) of crude oil per day. Over the 15 day period the modelling is run for this would result in a spill of 29,873 tonnes (35,775m3) of crude oil. Modelling was commissioned to determine the extent of the spill should a blow out occur. The results are presented below and in more detail in Appendix B. It should be noted that all modelling information provided is generic and illustrative only and not intended to be relied upon in any specific instance. This is because in practice any number of variables may impact on an oil spill or other environmental incident and as such should be addressed on an individual basis, taking account of the specific conditions encountered. The scenario was modelled using two types of models:

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Stochastic - A stochastic model, also known as a probability model shows the probability of where an oil spill may impact for defined periods of time for a range of prevailing wind directions. It represents the combination of spills from twelve different wind directions (this means that it does not represent the full extent of a given spill scenario). The model uses historical wind data to run a series of trajectories for the various wind directions. It then combines the results to produce an overall illustration of the probability of where oil might travel to in the defined period of time. This type of modelling is an important tool for determining the areas of coastline that could potentially be affected by a spill and therefore the best locations to place oil spill response equipment. Trajectory - A trajectory or deterministic model are used to predict the route of an oil slick over time and under certain metocean conditions. UK legislation requires two trajectory models are undertaken for each spill scenario investigated by the oil and gas industry; one trajectory using a 30 knot wind blowing towards the nearest stretch of UK coastline; and one trajectory using a 30 knot wind blowing towards the closest international boundary. Figure 6-1 shows the output of the stochastic model for the loss of 35,775m3 of crude oil as a result of a loss of well control. The model output illustrates the extent of the oil spill after 15 days for 12 prevailing wind directions and provides the probability of the spill reaching a particular area. For example, if during the collision the prevailing wind direction was towards the west-north-west, the diagram illustrates that there is a less than 10% probability of oil beaching on the west coast of the Shetland Islands. In this scenario, the probability of the oil also beaching in Norway would be significantly less, probably around 0%. Therefore, depending on the prevailing wind condition at the time of the event there is a 1% chance of oil beaching along the coastlines of the majority of countries bordering the North Sea (Figure 6-1 and 6-2). Modelling indicates that the spill will have beached on the UK coastline within 8 days and 10 hours and on the Danish coastline within 5 days and 17 hours. The spill will have completely dispersed within 417 days.

Figure 6-1: Stochastic model run – blow out of 35,775m3 of hydrocarbons over 15 days Wind rose

Key for stochastic output

Source: OSR (2011)

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Figure 6-2: Possible beaching locations

Source: OSR (2011)

6.4.2 Production

The tie-back of the Galia well to the FPSO via the Alma production centre will not result in any changes to the modelling for the worst case scenario during production of a full loss of containment from both the FPSO and export tanker due to collision (with each other). If this were to happen, a maximum of 5,830m3 (4,897 tonnes) of diesel and 100,000m3 (87,000 tonnes) of crude oil would be released instantaneously. The 100,000m3 of crude oil represents the maximum (larger) capacity of the export tanker as neither vessel will be full at the same time. Full details of the modelling undertaken for this scenario are included in the Alma ES.

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7 IMPACTS ON PHYSICAL ENVIRONMENT

To understand the potential impacts from a development on the environment, it is important to have a clear understanding of the present state of the environmental baseline. For the purposes of this report the environment has been split into three categories: physical, biological and human. This section covers the physical environment and has been organised to describe the following in the order below:

Describe the data sources used

Present baseline conditions for the environment

Identify potential impacts from the Galia development on the environment

Propose mitigation measures to curtail, limit or eliminate potential impacts

Assess the significance of the residual impacts if mitigation measures are implemented Gardline Geosurvey Limited (GGL) was commissioned to carry out geophysical and geotechnical rig site and pipeline route survey investigations (GGL 2011) in the Galia development area. This survey also incorporated an environmental baseline and habitats component (GEL 2011), to obtain location specific information. These surveys were used to inform the majority of Section 7, 8 and 9. Other data sources used are recorded at the beginning of each section.

7.1 AIR

7.1.1 Baseline Data Sources

The main sources of data for this section are:

UK National Air Quality Archive. http://uk-air.defra.gov.uk/ (UK National Air Quality Archive 2011)

UK Air Quality Archive – Background NOx, NO2, PM10 and PM2.5 Maps for LAQM and DMRB. http://laqm.defra.gov.uk/maps/maps2008.html (UK National Air Quality Archive 2009)

Met Office European model (56.0°N 3.14°E Jan 1998 - Nov 2008). Data acquired under licence for this project (Met Office 2011). 7.1.2 Existing Baseline

Air quality

In general, UK air quality has been improving since 1990. Emissions of NOx and SO2 have decreased by 46% and 82% respectively due to reduced emissions from road transport and power stations (Dore et al. 2008). Data on offshore air quality is limited due to the absence of air quality monitoring stations. However, these gases are generally of limited concern in the offshore sector given the distances to sensitive receptors i.e. communities

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on land or fixed installation. The Galia development is, at its closest 280 km from land and 38km from the nearest fixed installation (Clyde platform). Levels of primary pollutants, which are emitted directly into the atmosphere, tend to be highest around their sources i.e., in urban and industrial areas. Simple dispersion modelling undertaken for a 90 day exploration well in the Southern North Sea (SNS) (Gaz de France Britain 2005) demonstrated 3 3 concentrations of NOx and SO2 would be 0.0139 µg.m and 0.0009 µg.m respectively at 500m from the emission point, well below health and environmental guidelines. The modelling assumed that 15 tonnes of fuel would be consumed per day from the drilling rig and standby vessel, which is broadly similar to fuel use during drilling at Galia. The CNS, in which the Galia field development is located, is generally considered to be windier than the SNS and therefore it was considered that this modelling could be applied to the field development. Wind regime The wind regime affects the dispersion of atmospheric emissions and the trajectory of surface films. It generates the wave regime which contributes to the dispersion of discharges at the sea surface (and in extreme storms can contribute to dispersion at the seafloor). An understanding of the wind regime is therefore important in understanding the potential for aerial and aquatic dispersion of emissions and discharges from the development, oil spill trajectory forecasting and planning of wind-sensitive elements of oil spill response. A wind rose for the development area showing the annual prevailing wind directions is presented in Figure 7-1. Wind direction shows a wide distribution; the prevailing direction is south-westerly and winds from the northeast are comparatively uncommon. The strongest winds generally come from the sector southwest through to north. The data has been extracted from the UK Met Office European Model; purchased under licence for use on this project.

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Figure 7-1: Annual wind rose for the Galia area

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7.1.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect air quality are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 7-1: Air quality – potential impact identification Project Activity Aspect Potential impact Construction Physical presence and Exhaust gas emissions movement of vessels Localised deterioration in air quality Bulk storage and transfer Dust release during transfer Production Operation and maintenance of FPSO Localised deterioration in air Increased movement of export Exhaust gas emissions tanker and supply vessels quality Flaring during initial stages of production

7.1.4 Control & Mitigation Measures

EnQuest will ensure practical steps to minimise atmospheric emissions are taken. These include, but are not limited to:

Ensuring efficient operations by keeping all power generation equipment well maintained

Using cleaner lower emission fuels and monitoring fuel consumption

Stack heights will be in accordance with the relevant regulations

The emissions associated with power generation will be managed via a new Pollution Prevention Control (PPC) permit that will be applied for before production commences.

EnQuest are committed to keeping production flaring to the minimum required for operational purposes. 7.1.5 Residual Impact Significance Assessment

Residual impact assessment related to air quality was scoped out in Section 5.5.1.

7.2 CLIMATE CHANGE

7.2.1 Baseline Data Sources

This section principally references the following secondary data sources:

UK Policy Planning Statement 25: Development and Flood Risk. Revised March 2010 (CLG 2010).

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UK Climate Projections website (http://ukclimateprojections.defra.gov.uk) (2009)

UK Climate Impacts Programme website (http://www.ukcip.org.uk/) (2011) To help organisations to assess their vulnerability to climate change and plan appropriate adaptation strategies the UK Government established the UK Climate Impacts Programme (UKCIP). The programme established scenarios for future climate change in the UK, taking in to consideration current and future mitigation measures to be implemented by the UK Government. These scenarios have been used to predict what the future environmental baseline at the Galia development will be as the environment responds to climate change.

7.2.2 Existing Baseline

There is an increasing body of evidence showing that global climate is changing as a consequence of human actions. There is potential for past, present and future emissions of greenhouse gases to cause significant global climate change during the next century. Sea level may continue to rise, having implications for wave heights, wave propagation, storm events, flooding and coastal erosion. Sea temperatures, salinity and nutrient levels may also rise with implications for biological processes. The magnitude of sea level rise is dependent on greenhouse gas emissions, the sensitivity of the climate system and the relative local vertical movement of the surrounding land masses. The UK land mass is generally falling in the south-east and rising in the north and west. The UK climate projections predict an absolute sea level rise of between 2.8mm and 3.8mm per year for the period of 1990 to 2025 and between 6.1mm and 8.1mm per year for the period of 2025 to 2055, for UK marine areas (UKCP 2009). In addition, Table 7-2 below shows the recommended contingency allowances for net sea level rise from 1990 until 2115 (CLG 2010). Table 7-2: Recommended contingency allowances for net sea level rise Net Sea Level Rise (mm/yr) Relative to 1990 Administrative Region 1990 to 2025 to 2055 to 2085 to 2025 2055 2085 2115 East of England, East Midlands, London, South East England (south of 4.0 8.5 12.0 15.0 Flamborough Head) South West 3.5 8.0 11.5 14.5 North West England, North East 2.5 7.0 10.0 13.0 England (north of Flamborough Head) Notes: 1. For deriving sea levels up to 2025, the 4mm/yr, 3mm/yr and 2.5mm/yr rates (covering the three groups of administrative Regions respectively), should be applied back to the 1990 base sea level year. From 2026 to 2055, the increase in sea level in this period is derived by adding the number of years on from 2025 (to 2055), multiplied by the respective rate shown in the table. Subsequent time periods 2056-2085 and 2086-2115 are treated similarly. 2. Refer to Defra FCDPAG3 Economic Appraisal Supplementary Note to Operating Authorities – Climate Change Impacts, October 2006, for details of the derivation of this table. In particular, Annex A1 of this Note shows examples of how to calculate sea level rise.

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3. Vertical movement of the land is incorporated in the table and does not need to be calculated separately. Source: CLG 2010 Table B.1 It is predicted that a rise in sea level will change wave heights due to increased water depths, and may change the frequency, duration and severity of storm events. The Government suggests that a 5% sensitivity allowance should be added to offshore wind speeds and wave heights by 2025 (CLG 2010). Sea temperatures in the NNS may rise by 1.0°C by the 2020s and by 1.5 - 3.0°C by the 2080s (under low and high emissions scenarios respectively) (UKCIP 2002). The UK climate predictions for the period 2070 – 2099 indicate that the mean sea surface water temperature will be between 8°C and 17.0°C in the project area (UKCP 2009).

7.2.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect climate change are presented below in Table 7-3. As all of the identified activities have been determined (by the EIA) to have potential for residual impact, they are all shown in bold. Table 7-3: Climate change – potential impact identification Project Activity Aspect Potential Impact Construction Physical presence and movement of Exhaust gas Loading of greenhouse gases e.g., vessels emissions CO2, CH4 Production Operation and maintenance of FPSO Exhaust gas Loading of greenhouse gases e.g., emissions CO2, CH4 Increased movement of export tanker and supply vessels Flaring during initial stages of production 7.2.4 Control & Mitigation Measures

The measures to reduce atmospheric emissions which were discussed under air quality (Section 7.1.) also apply to emissions of CH4 and CO2. In addition, EnQuest are committed to ensuring the minimum amount of gas is flared during production.

7.2.5 Residual Impact Significance Assessment

Residual impact assessment related to climate change was scoped out in Section 5.5.1.

7.3 WATER RESOURCES

7.3.1 Baseline Data Sources

This section principally references the following secondary data sources:

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nd 2 Strategic Environmental Assessment (SEA) technical reports including information on water quality (DTI 2001a,b)

Quality Status Report (OSPAR Commission 2010)

EnQuest (2012). Knightsbridge Project: Alma & Galia Field Development Basis of Design. Document No. ENQ-KN501-PM-000- BOD-0002 Revision B3 7.3.2 Existing Baseline

Mixing of North Atlantic seawater and freshwater run-off from land, results in several water masses occurring in the North Sea with characteristic temperature and salinity distribution, residual current patterns and stratification. The Galia field development area is situated within the CNS water mass. Density stratification in the CNS is well developed in the summer months, with the relative strength of the thermocline determined by solar heat input and turbulence generated by wind and tides. It breaks down after September however, due to increasing frequency and severity of storms and seasonal cooling at the surface (DTI 2001a). Temperature and salinity characteristics in the Galia field development area are indicated in Table 7-4. Table 7-4: Physical characteristics of the sea water in the Galia field Water parameter Approximate value Minimum 0 º C Sea surface temperature1 Maximum 19 º C Minimum 5 º C Bottom temperature1 Maximum 9 º C Sea surface salinity2 35.048 psu Bottom salinity2 35.052 psu Source: 1 Enquest (2012) 2 Analysis of data obtained from International Council for Exploration of the Sea (http://www.ices.dk/ocean/aspx/HydChem/HydChem.aspx)

7.3.2.1 Water quality

There are many sources of contamination entering the North Sea which can affect water quality, which include riverine inputs, coastal run-off and offshore activities. Pollutants of the water column can be separated into the following groups:

Organics (including hydrocarbons)

Trace metals

Radionuclides To inform the SEA process a review of chemical contamination was undertaken by CEFAS and the Fisheries Research Service (FRS, now Marine Scotland) to identify background levels and trends in the North Sea (DTI 2001b). The review indicated that (i) inshore estuaries and (ii) coastal sites, subject to high industrial usage, show the highest levels of chemical contamination (Table 7-5, DTI 2001a). Offshore waters generally contain lower concentrations of polyaromatic hydrocarbons (PAH) and total hydrocarbons (THC). For example,

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PAH concentrations exceeding 1µgl-1 were found in four UK eastern coast estuaries compared to concentrations between 0.018-0.09µgl-1 offshore in the German Bight (DTI 2001b). Similarly, Law et al. (1994), in DTI 2001b) found that THC concentrations offshore are generally very low (2.5µgl-1) compared to levels found in some estuaries (64µgl-1) (DTI 2001b). High concentrations of THCs, in the range of 30 - 43µgl-1, are found in the immediate vicinity of some offshore oil and gas installations, although concentrations generally fall to background levels within a short distance from the discharge point (DTI 2001b). Table 7-5: Summary of North Sea surface waters contaminant levels THC PAH PCB Ni Cu Zn Cd Hg Location (µgl-1) (µgl-1) (ngl-1) (µgl-1) (µgl-1) (µgl-1) (ngl-1) (ngl-1) Oil & Gas 1 - 43 ------Installations Estuaries 12 - 15 >1 30 - - - - - Coast 2 0.02 - 0.1 1 - 10 0.2 - 0.9 0.3 - 0.7 0.5 - 2.2 10 - 32 0.25 - 41 Below Offshore 0.5 - 0.7 - 0.2 - 0.6 0.3 - 0.6 0.5 - 1.4 10 - 51 1.6 - 69 detection Source: DTI 2001b Historically there have been two main sources of contaminants from oil and gas activity in the North Sea: produced water and drill cuttings. With the introduction of OSPAR decision 2000/3, hydrocarbon input from drill cuttings has been essentially eliminated, as OBM is no longer discharged to sea. However, there is a legacy of contamination which remains, in the form of historic cuttings piles around some installations, especially in the CNS and NNS (DTI 2001b). Produced water is now the main contamination source, containing both hydrocarbons and chemicals. Historic research has shown that, due to the rapid dilution and low concentrations and low toxicities of the pollutants, produced water discharges in the North Sea have a low potential for biological impact (Wills 2000). Dilutions required for no observed effect concentration (NOEC) are achieved within five minutes between 10 and 100m from the discharge point. The nearest platform is Clyde, which is 38km north-west of the Galia drill centre, and at this range it is not conceivable that Galia would have a material impact on the area causing the NOEC to be exceeded. As a result, it is considered that as exposure times are short, acute toxic effects on species are unlikely (Wills 2000). Long term or chronic effects are also unlikely given the minimal contaminant levels in produced water (UKOOA 1999). It has been suggested that contaminants in discharges may affect planktonic larvae (Wills 2000), but more work is required by the industry on the amounts, fates and effects of toxic heavy metals in produced water before any significant conclusions can be drawn.

7.3.2.2 Tidal and other currents

Speed and direction of currents has a direct effect on the transport, dispersion and ultimate fate of any discharges into the marine environment. Strength of current determines the rate of dispersion and vertical mixing of discharges into the water column. Figure 7-2 (adapted from OSPAR 2000 after Turrell 1992) is a schematic diagram of general circulation in the North Sea. The broad pole-ward transport of Atlantic Water along the continental slope (the “Slope Current”) branches

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along the western slope of the Norwegian trench and also spills onto the continental shelf around the Shetland Islands. The approximate location of the Galia development is indicated on the diagram. At Galia, tidal current speeds are relatively high compared to other areas of the North Sea. Average speeds of 0.2ms-1 at surface indicate a flushing time of 1.5 hours for a column of water 500m in diameter. Near bed speeds are approximately half of surface speeds. Current speeds may be slower in summer. The current speeds at the Galia field are summarised in Table 7-6. Table 7-6: Summary of tidal current speeds at the Alma field Depth (m) 1 year (ms-1) 50 year (ms-1) 0 (surface) 0.56 0.68 19.5 0.56 0. 68 39 0.56 0. 68 62.4 0.50 0.60 74.1 0.41 0.49 78 (seabed) 0.33 0.40 Source: EnQuest (2012) Figure 7-2: General current circulation in the North Sea

Source: OSPAR 2000 after Turrell et al. (1992)

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Storm surges will also occur occasionally but are short-lived. They occur when a deep depression crosses the NNS or Norwegian Sea and manifest as a tide- like wave progressing southward through the North Sea. This temporarily increases water levels and current speeds. Storm surge currents can exceed speeds associated with tides.

7.3.2.3 Waves

The wave regime in the area contributes to initial dispersion of any surface discharges and therefore needs some consideration in the assessment of a development’s impact on the environment. Wave heights are among the greatest in the North Sea (100-year extreme significant wave height (Hs) is 13.6m and 1-year extreme is 9.4m) (See Table 7-7). The North Sea is considered to be frequently “rough” from October to March (DTI 2001a). Table 7-7: Wave characteristics at Alma Parameter 1 Year 50 Year 100 Year Hs (m) 9.4 12.9 13.6 Tz (s) 9.5 11.1 11.4 Hmax (m) 17.4 24 25.2 Tmax (m) 10.7 12.5 12.9 Source: EnQuest (2012)

7.3.3 Potential Impact Identification

The construction and production activities at Galia have the potential to affect water quality. Additionally, tides, currents and waves will have an indirect affect on some project aspects and their impacts on environmental receptors, e.g., by influencing the dispersion of chemical discharges. The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect water quality are presented in Table 7-8 below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 7-8: Water resources – potential impact identification Project Activity Aspect Potential Impact Construction Discharge of sewage, grey Physical presence and movement of water, food waste and drainage vessels water Bulk storage and transfer Dust release during transfer Localised Discharge of chemicals deterioration in (including WBM) water quality Drilling of wells Discharge of reservoir hydrocarbons Discharge of chemicals Installation of flowlines Concrete mattressing and rock Increased

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placement suspended Trenching and backfill sediment loads & turbidity Physical presence of subsea infrastructure and flowlines Production Discharge of produced water Discharge of chemicals Localised Operation and maintenance of deterioration in FPSO Discharge of sewage, grey water, food waste and drainage water quality water Accidental Events Chemical / hydrocarbon release (< 1 tonne) Localised Chemical / hydrocarbon release (1- Diesel, crude or chemical spill deterioration in 10 tonnes) (including OBMs) water quality Chemical / hydrocarbon release (>10 tonnes) 7.3.4 Control & Mitigation Measures

All project associated vessels will have and implement a written waste management plan compliant with the International Convention for the Prevention of Pollution from Ships (1973/1978) (MARPOL 73/78) and its Annexes. As per Regulation 9 (Annex V, 1995) all vessels over 400 tonnes will have and maintain a Garbage Record Book. The plan will establish designated waste storage areas and will ensure all waste is contained and stored away from open drains. All liquid waste will be stored with secondary containment. Paper and food wastes will only be discharged beyond 12nm from shore. No plastics or plastic containing materials will be disposed at sea, regardless of location. Solid wastes will be compacted where possible and stored for appropriate disposal ashore. Household products and construction chemicals (i.e., chemicals used during completion drilling and pipeline commissioning) which are environmentally benign will be preferentially selected. Chemical use will be monitored daily during construction to allow more refined and efficient use. Where possible, products will be recycled or reinjected to minimise discharge quantities. Only chemicals approved under the relevant Offshore Chemicals (Amendment) Regulations (OCR) chemical permit will be discharged, i.e., PON15B, PON15C or PON15D. Under normal operating conditions, all produced water from the Galia development will be re-injected into the water-injection wells (see Section 5.3.4). It is only if the system trips, that there is a possibility that produced water will be discharged overboard from the FPSO. To ensure any discharges in such a situation are regulatory compliant all produced water will be processed so that OIW concentrations are at least 30mgl-1. Accidental spills will be kept to a minimum through training, storage/handling procedures and good housekeeping. Management controls will be in place to eliminate accidental and bunkering spills e.g., only bunkering during good

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daylight conditions and in good weather. EnQuest will have an approved OPEP in place to respond to accidental hydrocarbon spills associated with the proposed drilling and production activities. These will be prepared in accordance with the Oil Pollution Preparedness, Response and Co-operation Convention Regulations 1998, the Offshore Installations (Emergency Pollution Control) Regulations 2002 and updated guidance provided by the DECC in response to the Macondo Prospect incident in the Gulf of Mexico. The impacts of hydrocarbon spills are greatest for seabirds and as such the mitigation measures for fuel and crude oil spills are discussed in detail in Section 8.4. EnQuest considers the minimisation of chemical usage a priority and will actively seek products that are deemed to have minimal environmental impacts (i.e., low toxicity, low bioaccumulation potential and high biodegradability).

7.3.5 Residual Impact Significance Assessment

7.3.5.1 Increased suspended sediment loads

Three activities during the construction phase have the potential to disturb seabed sediments, increasing suspended sediment loads in the water column. These are:

Placement of subsea infrastructure

Trenching the flowlines into the seabed

Placement of concrete mattressing Although the placement of subsea infrastructure, concrete mattresses on the seabed will disturb the seabed, it is expected that suspended sediments will return to normal as soon as the activity ceases. Of these activities, trenching has the potential to create the largest disturbance. It is estimated that approximately 6km of flowline will be trenched per day. Sediment will be piled on each side of the trench during the initial cutting of the trench. This sediment will then backfill into the trench through normal seabed processes. Of the sediment suspended, the heavier sediment is likely to settle out of suspension quickly (within a few minutes of suspension) in a thin layer in close proximity to the trench, whilst the lighter sediment will remain in suspension, potentially for days, and will be transported by currents away from the pipeline route. It will settle out, but slowly, over a wider area, ensuring a thinner deposition (possibly undetectable). Limited research has been conducted into the effects of pipeline installation on sediment loading, but a comparable impact on water quality can be found in the marine aggregate industry. Often, as marine aggregate is extracted, the water/aggregate mix is passed over coarse mesh screens to increase the gravel content. The removed sand and silt is rejected overboard where it forms a sediment plume in the water column. The plumes are created over a six to eight hour period, depending on the size of the cargo. Monitoring has shown that the increased suspended sediment loads are transient, with concentrations of sediments returning to background levels within 6-7 tidal cycles (Marine Aggregate Licence Area 430: East of Southwold, Compass Hydrographic Surveys Ltd 2004). The suspended sediment concentrations created by activities at Galia are not as high as those created by the aggregate industry. Trenching activity will be of very short duration, of the order of 4 days, so any disturbance will be transitory,

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with concentrations returning to background levels within two or three days. Consequently, no residual impact on the water column is envisaged

7.3.5.2 Deterioration in water quality

The main emission with potential to contribute to deterioration in water quality is produced water. This will only occur occasionally, during outage of the water injection system at Alma, and under these circumstances, the discharge (identified in Section 5.5.2) is tabulated below. Table 7-9: PW discharge during production Project Activity PW (m3d-1) Oil (kgd-1)

Production 1,521 45.6

Table 7-9 shows daily emissions and it should be noted that such emissions will be infrequent as PW will normally be re-injected into the Alma WI wells. Given the prevalent metocean conditions in the project area (e.g., winds, waves, tides and currents), the short-time scale of the construction period and the small cumulative volume of discharges, the marine environment will be able to rapidly assimilate the discharges through natural bacterial action. Any degradation in water quality will be transient (limited to a few hours after the discharge) therefore there is unlikely to be any long term change in the chemical composition of the surrounding water column as a result of the discharge. Consequently, it is considered that the impact on water resources is likely to be minimal.

7.4 SEABED CONDITIONS

7.4.1 Baseline Data Sources

This section principally references the following primary and secondary data sources:

Gardline Geosurvey Limited (GGL) (2011). Galia Site Survey UKCS 30/24. Ref 8826.1

Gardline Environmental (2011) Galia Sites and Pipeline Route Surveys UKCS 30/24 and 30/25: Environmental Baseline Report. Ref 8826.5

BGS (2004). Technical Report produced for Strategic Environmental Assessment – SEA2: North Sea Geology. TR_008.

DTI (2001a). Strategic Environmental Assessment of the Mature Areas of the Offshore North Sea - SEA 2. 7.4.2 Existing Baseline

7.4.2.1 Bathymetry and seabed topography

The site survey reports indicate that the seabed is essentially flat across the entire Galia development area (Figure 7-3). Water depths range locally from 78.3m lowest astronomical tide (LAT) to 79.8m LAT (GGL 2011).

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7.4.2.2 Seabed geology

The shallow geology encompasses the formation sequences, the presence of formation members and outlines sequence trends in the development area. This data was obtained in a site specific survey undertaken by Gardline (2011). Gardline surveys of the development area identified the shallow geology sequences. The top layer of the development area comprises a thin veneer of Holocene sand which is expected to be <2m thick throughout. This layer overlies the Fitzroy Member of the Forth Formation (firm to very stiff sandy gravelly clay with interbedded dense silty sand). These sediments infill a complex channel system up to 56m deep though over the flanks, the sediments are frequently less than 5m thick. Following this, the Fisher Formation extends to depths of 40m and Ling Bank Formation to depths of 124m below the seabed (GGL 2011). In places in the west and northeast, the Forth Formation sediments are thin to absent leaving the underlying Fisher Formation sub-cropping seabed. There is no evidence that these sediments actually outcrop at the seabed (GGL 2011).

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Figure 7-3: Bathymetry at Galia drill centre

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7.4.2.3 Surface sediments

Sediment located at or within the upper 1m of the surface of the seabed is considered as surface sediment. This section provides an overview of surface sediment typical to the wider region and details the site specific surface sediment characteristics obtained during Gardline surveys (2011) of the development area. Seabed sediment in the North Sea derives from the latter epoch of the Quaternary period, the Holocene (the past approx. 10,000 years through to the present). These sediments are distributed by historical and present hydrodynamic processes of the North Sea (BGS 2004). The surface sediment of the CNS is broadly characterised by mud and sands. Sediment type correlates with water depth, in deeper waters sediment is typically muddier with a less proportion of sand and in shallower depth sediment is sandy with a low mud content. Surface sediments of the CNS are typically >10,000 years old (Holocene epoch) (DTI 2001a). The Galia site survey (GGL 2011) identified surface sediments consisting of Holocene sands with scattered small depressions accumulating shells (Figure 7-4). The sediments are characterised as very loose to loose with a poor to moderate degree of sorting. Particle size analysis (PSA) from eleven stations in the development area identified sediments typically range from fine to very fine (<63µm) in grain size. Sediment >2mm (gravels) were not identified in the area. Overall the PSA results support the conclusion of featureless and generally homogeneous sediment across the site (Gardline 2011). Figure 7-4: Example of seabed sediments from survey

Source: GEL 2011 7.4.2.4 Sediment contamination

Any sediment contamination in the Galia area is most likely to be derived from past oil and gas activity, e.g. drill cuttings and produced water. Sediment within an area of 500m around most offshore infrastructure is likely to be contaminated with hydrocarbons and a range of other compounds i.e., heavy metals (DTI 2001b). Produced water is the primary source of contamination now, with replacement methods in place reducing hydrocarbon contamination from drill cuttings. The organic content of sediment and particle size relates to the transportation and retention of contaminants. Sands and coarse sediment typically have a low organic content, whereas fine sediments typically exhibit

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higher organic content and are likely to be readily picked up and transported to lower energy environments (GGL 2011). Sediment samples were obtained during the Galia site surveys (Gardline 2011) at eleven stations and were analysed for hydrocarbon and heavy metal contamination. Results indicated that there is hydrocarbon contamination across the site. Total hydrocarbon content (THC) in samples ranged from 7.3µg.g-1 to 15.8µg.g-1, with a mean THC of 9.9 µg.g-1. Typically, THC for the North Sea is 9.51µg.g-1. Higher THC recordings were obtained in fine sediments in deeper waters. This is considered to be due to the low energy environment where contamination is not so widely distributed. Furthermore, the site is a historic field development area (Duncan development) where drilling and production has been undertaken. Table 7-10 provides details of heavy metal concentrations recorded at the Galia development in comparison to the surveys carried out at the Alma development (Gardline 2011b) in 2007, 2010 and 2011. This table demonstrates that the concentration of heavy metals in sediment in the area recorded since 2007 has remained relatively consistent over this four year period and are comparable to the Galia development. In all cases, except for Pb at Galia, maximum concentrations of metals reported were below the OSPAR (2005) background concentrations for the North Sea, where these are available. Given that this a developed site, the relative consistency of the heavy metal concentrations over this timeframe suggests that current speeds are insufficient to disturb/remobilise/flush out the historical contamination. Therefore, heavy metal contamination in the sediment is likely to remain at a constant level.

Table 7-10: Heavy metals in sediment (µgg-1) Sediment metal concentration Metal Galia Alma OSPAR 2005 Gardline 2011 Gardline 2011 GEL 2010 GEL 2007 Background Al 16,120 13,687 - 14,300 - As 4.1 5 4.2 4 15 Ba 340 571 235 257 - Ba1 195 656 194 227 - Cd 0.1 0 0.1 0 0.2 Cr 23.4 17 6.8 13 60 Cu 10.6 6 11 4 20 Fe - 5,503 - 5,353 - Hg2 0.01 0 0.03 0 0.05 Ni 5.9 4 3.4 4 30 Pb 56.4 18 10.9 13 25 Sn 1.5 1 1 - - V 26.7 26 8.6 15 - Zn 22.5 20 16.8 20 90 Ba1. Concentrations determined following fusion with lithium metaborate and extraction with nitric acid Hg2. Concentrations determined following nitric acid digest preceded by digestion of organic matter with hydrogen peroxide Note: Blank cells represent no available data Source: Gardline (2011a & b)

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7.4.2.5 Seabed features

Numerous wells are recorded as being present within the survey area; however no objects with height representing wellheads were observed at seabed on sonar data. The majority of wellhead positions were confirmed by magnetometer anomalies (GGL 2011). Areas of disturbed seabed are associated with six of the wells. One area of disturbed seabed is associated with a magnetic anomaly where a number of seabed scars converge, approximately 2.1km directly east of the GAL-2 location. This is not associated with any known well in the area (GGL 2011). Two areas of disturbed seabed occur in the north-eastern corner of the survey area; both interpreted as (significantly degraded) wrecks. The southernmost wreck correlates with wreck ID 3277. The northernmost does not correspond with any known wreck. Both of these are at a distance of >2.5km from all locations. Articles of debris e.g., bits of cable and pipe, related to disused/abandoned wells and fishing gear where identified. Depressions and scars are thought to be associated with the removal of infrastructure during the decommissioning of the Argyll/Ardmore and Duncan fields (GGL 2011). No evidence of reefs, eyed pockmarks or Annex I habitats (EC Habitats Directive 92/43/EEC) was apparent in the survey data (SSS or multi-beam echo sounder (MBES)).

7.4.2.6 Sediment mobility

Sediment mobility refers to the behaviours of the near and at-surface sediment that composes the seabed, as influenced by currents, waves and storm conditions. Water depths in the vicinity of the development range between 78.3m and 79.8.3m LAT. At these depths unconsolidated sediments are unlikely to be affected by wave stirring or storm induced currents (GGL 2011). Typical to the CNS, the Galia development area is therefore characterised by very low sediment input and re-working of sediment by near bottom currents (BGS 2004).

7.4.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect seabed conditions are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 7-11: Seabed conditions – potential impact identification Project Activity Aspect Potential Impact Construction Physical presence and Disaggregation of surface Anchoring movement of vessels sediments Change in seabed Discharge of cuttings topography Drilling of wells Discharge of chemicals (including WBM) Sediment contamination Discharge of reservoir hydrocarbons Discharge of chemicals Compaction and Physical presence of subsea disaggregation of surface infrastructure and flowlines sediments Change in surface sediments Installation of flowlines Trenching and backfill Change in seabed topography leading to changes in sediment transport pathways Concrete mattressing and rock Change in seabed placement topography Production Operation and maintenance Discharge of produced water Sediment contamination of FPSO Discharge of chemicals Accidental Events Overboard loss of Dropped objects Scour around objects equipment or waste Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical spill Sediment contamination release (1-10 tonnes) (including OBMs) Chemical / hydrocarbon release (>10 tonnes)

7.4.4 Control & Mitigation Measures

Footprints on the seabed will be minimised where possible. Concrete mattressing will be placed on the seabed in such a manner that will minimise seabed disturbance. To reduce the impact of chemical operations on the seabed, chemicals that are environmentally benign will be preferentially selected. All discharges will be risk assessed and will be within permitted levels. OBM will be recycled throughout the drilling programme to minimise usage and will be shipped to shore on well completion. No OBM will be discharged to sea.

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Mitigation against accidental events includes conducting a debris clearance survey prior to each rig move, ensuring that any significant objects are removed. Regular inspections will be undertaken to establish that all equipment is in good working order and accidental spills will be kept to a minimum through training, good housekeeping and through storage/handling procedures. Sumps and drains should catch accidental spill releases, and management controls will be in place to eliminate bunkering spills (for example, only bunkering during good daylight conditions and in good weather). EnQuest will also ensure that a field specific OPEP is in place for the drilling and production phases.

7.4.5 Residual Impact Significance Assessment

7.4.5.1 Contamination of sediments

The EIA concluded that an unplanned hydrocarbon or chemical release of 1-10 tonnes had the potential to contaminate seabed sediments, with a residual impact of minor significance. A spill of <1 tonne at the surface is unlikely to contaminate seabed sediments. As discussed in Section 6.2.1 the possibility of a loss of containment has an estimated frequency of 32 incidents per annum and, it has been estimated that there is a 2.5% likelihood of a spill greater than 0.1 tonnes and a 0.5% likelihood of a spill between 1 and 10 tonnes occurring during drilling at Galia. If this was to occur, it is possible that sediments may become contaminated with hydrocarbons, which are likely to persist for some time. It is possible that contaminated sediments could be subsequently dispersed, in effect reducing the localised concentration levels. Small spills are unlikely to be noticeable against current baseline levels below background levels.

7.4.5.2 Physical disturbance causing a change to surface sediments

As summarised in Section 5.5.3, a number of project activities will impact the seabed either through compaction of surface layers or by physical disturbance, e.g., displacement and redistribution. A maximum of 0.33km2 of seabed will be disturbed by construction activities. This is comprised of 0.32km2 of disturbance combined with up to 0.003km2 of coverage by drill cuttings. The cuttings pile is comprised of WBM and will have low toxicity potential. In addition as Galia is located within the CNS it can be expected that the cuttings pile will erode within 5-10 years UKOOA 1999). Activities which physically penetrate surface sediments, e.g., anchoring and trenching, will likely leave the seabed visibly disturbed. However any disturbance will be quickly backfilled and degraded by the current regime in this area of the CNS. The presence of the concrete mattressing and rock protection on the seafloor may cause a slight variation in the local hydrodynamics. This could potentially cause slight scour and/or deposition in the immediate vicinity of the mattressing. This is of negligible significance in the wider scope of impacts and the mattresses will be removed from the development area during field decommissioning.

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8 IMPACTS ON BIOLOGICAL ENVIRONMENT

This section describes the baseline biological environment, the impacts the Galia development will potentially have on this environment, how any impacts will be mitigated and qualifies the significance of any residual impacts. It follows the same structure as Section 7 and uses the methodology established in Section 3. The biological environment has been divided up as follows:

Plankton (Section 8.1)

Benthic communities (Section 8.2)

Fish and shellfish (Section 8.3)

Seabirds (Section 8.4)

Marine mammals (Section 8.5)

Protected sites and species (Section 8.6)

8.1 PLANKTON

8.1.1 Baseline Data Sources

This section principally references the following data source:

Strategic Environmental Assessment of the Mature Areas of the North Sea (SEA2) (DTI 2001a) 8.1.2 Existing Baseline

Plankton can be classified as phytoplankton or zooplankton, representing plants and animals respectively. They range from microscopic life to large species, such as jellyfish, which live freely in the water column and drift with the water currents. The plankton communities in the vicinity of the Alma development are expected to be typical of those of the CNS. Strong seasonal abundance patterns, governed by light and nutrient levels, are observed across the region. Favourable conditions lead to a spring bloom in phytoplankton (April-May) followed by a later bloom in the zooplankton, supported by the increased phytoplankton abundance. However, stratification of the water column limits plankton growth once available nutrients have been exhausted in the surface water. A second bloom occurs in the autumn when thermal stratification breaks down, allowing mixing of surface and nutrient rich deep waters. Superimposed on the annual cycle of plankton abundance in the North Sea are changes in community structure that occur over longer periods of time. For example, continuous plankton recorder (CPR) surveys have shown that phytoplankton biomass has increased over the last four decades over much of the North Sea. Hydroclimatic long period climate cycles such as the North Atlantic Oscillation have also been shown to play an important role in altering the plankton dynamics of the North Sea. Current research suggests that these have a greater impact on the planktonic communities of the North Sea than anthropogenic factors (DTI 2001a).

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8.1.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect plankton are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 8-1: Plankton – potential impact identification Project Activity Aspect Potential Impact Construction Organic enrichment leading Discharge of sewage, grey Physical presence and to raised biological oxygen water, food waste and movement of vessels demand. May change drainage water balance of food chain. Discharge of chemicals (including WBM) Drilling of wells Discharge of reservoir Potential toxic effects hydrocarbons Installation of flowlines Discharge of chemicals Production Discharge of produced water Operation and Potential toxic effects Discharge of chemicals maintenance of FPSO Organic enrichment leading Discharge of sewage, grey to raised biological oxygen Increased movement of water, food waste and demand. May change export tanker and supply drainage water vessels balance of food chain. Accidental Events Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical Potential toxic effects release (1-10 tonnes) spill (including OBMs) Chemical / hydrocarbon release (>10 tonnes) 8.1.4 Control & Mitigation Measures

Measures outlined in Section 7.3.4 adopted to reduce and/or eliminate the toxic impacts of the development on water quality will also mitigate the potential impacts on plankton. These have not been repeated here but are listed in the previous sections and Sections E of Appendix A. In addition, all chemical discharges will be risk assessed and within the DECC permitted levels as per the relevant Offshore Chemicals (Amendment) Regulations (OCR) chemical permit i.e., PON15B, PON15C or PON15D.

8.1.5 Residual Impact Significance Assessment

During construction and production, permitted chemicals will be discharged to sea either at the seabed or at sea level depending on their use. Some

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chemicals used have the potential to cause toxic harm when discharged e.g., biocides or oxygen scavengers. In addition, if an accidental spill of greater than 10 tonnes of hydrocarbons or chemicals were to occur it is expected that the plankton community would suffer from toxic effects. The metocean conditions in the region will ensure chemical discharges are rapidly diluted and dispersed, minimising the persistence of any effects. As such, the impacts of construction and production activities on plankton have been assessed as having no residual impacts after mitigation. The impact of an accidental spill of greater than 10 tonnes of hydrocarbons or chemicals has been assessed as having a minor impact after mitigation.

8.2 BENTHIC COMMUNITIES

8.2.1 Baseline Data Sources

This section principally references the following primary data source:

Gardline Environmental (2011) Galia Sites and Pipeline Route Surveys UKCS 30/24 and 30/25: Environmental Baseline Report. Ref 8826.5 8.2.2 Existing Baseline

During the 2011 Galia site survey eleven stations were selected for investigation with a camera system and for sampling with a 0.1m2 day grab. Two samples were taken from each station. The stations were selected to investigate sediments close to the main proposed infrastructure locations (GAL- 1, GAL-2, GAL-RW and the GAL-1 to Northern Drill Centre (NDC)) Samples were also taken near the proposed (but now discounted) GAL-1 to Southern Drill Centre (SDC). Three stations were located 50m south of the respective GAL locations, four were located on the pipeline routes (two on each) whilst one station was located on a randomly selected area of dominant seabed type. One station was located in a patch of high reflectivity not associated with a historical well in order to ground truth the geophysical interpretation. This was revealed to be a well degraded wreck that was unsuitable for grab sampling. An additional station was then added approximately 110m east of this area. One station was also selected to the far north-west of the site to act as a reference site (GEL 2011). Fauna observed during the environmental baseline survey (GEL 2011) came from 5 main taxonomic groups: polychaetes, crustaceans, molluscs, echinoderms and “other”. The “other” taxa was comprised of Platyhelminthes (flat worms), Nermertea (ribbon worms), Phoronida (horseshoe worms), Hemichordata (acorn worm), Chordata (solitary ascidian) and two taxa each of Sipuncula (peanut worm) and solitary Cnidaria (GEL 2011). Overall, 56,189 individuals were recorded across twenty samples, of which 46,640 were juveniles and represented 83% of the overall population at the Galia location. As juveniles do not present a realistic reflection of year round fauna (due to high mortality levels) but are a valid part of the community, statistical analysis was carried out on both the full set (juvenile and adult) and adult only data sets. The full set of macrofauna data was dominated by echinoderms and accounted for c.82% of all individuals identified. Polychaetes were second dominant in the full set of data, however once the juveniles were removed, the polychaetes dominated (c.75%) with molluscs second. Once the

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juveniles (echinoderms) were removed, the statistics suggested that the community is generally uniform (GEL 2011). Table 8-2 shows the contributions of the gross taxonomic groups. Table 8-2: Contributions of the gross taxonomic groups Individuals Taxa Proportional Abundance Proportional Group Abundance Contribution Contribution (%) (%) Full Data Set Annelida 8,023 14 97 46 (Polychaeta) Arthopoda 662 1 46 22 (Crustacea) Mollusca 1,326 2 42 20 Echinodermata 45,786 82 16 8 Others 392 1 9 4 Total 56,189 100 210 100 Adult only Data Set Annelida 7,142 75 86 48 (Polychaeta) Arthopoda 644 7 42 24 (Crustacea) Mollusca 1,070 11 31 17 Echinodermata 304 3 11 6 Others 389 4 9 5 Total 9,549 100 179 100 Source: GEL 2011 In the full data set, 38 taxa were present at every station sampled, with 17 of these taxa present in every sample taken. The most abundant species in the full data set, both overall and in a single sample, was Echinoidea (juv), with 42,404 individuals present across the survey area and 4,926 individuals present in a sample from ENV7 (MFB). In the adult only data set, Pholoe assimilis was the most abundant species, with 2,112 individuals across the survey area, however the polychaete Paramphimone jeffreysii was the most abundant species in one sample, with 282 individuals in a sample from ENV7 (MFB). Both species are generally typical of North Sea benthic communities. P. jeffreysii is commonly found in sublittoral sands and muddy sands and is restricted to the deeper (>50m) parts of the central and northern North Sea (GEL 2011). It is also thought to be highly tolerant of hydrocarbon contamination (Olsgard and Gray, 1995). Both Pholoe sp. and P. jeffreysii are known to occur in areas if slight organic enrichment from drill cuttings (Connor et al., 2004). The presence of these species cannot be assumed to be as a result of contamination across the survey area (GEL 2011). The main species present in the project area are also known to be generally tolerant of increased levels of suspended sediments and low levels of smothering, but are generally intolerant of displacement (GEL 2011). In contrast, 64 taxa from the full dataset were found at only one station, with 62 of these taxa found in only one sample, 48 of which (23% of total taxa) were represented by a single individual. This is indicative of an absence of any

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notable contamination or disturbance, as under such scenarios it is expected that the taxa would be represented by a high abundance of a limited group of tolerant species (GEL 2011). Table 8-3 shows the top 10 species seen during the survey. Table 8-3: Species ranking Rank Total Total Score Abundance Species/Taxon rank Fidelity abundance score Full Data Set 1 1 Echinoidea (juv) 100 1.00 42,404 2 2 Ophiuroidea (juv) 87 0.97 3,002 3 3 Pholoe assimilis 77 0.96 2,112 4 4 Paramphinome jeffreysii 73 1.04 1,909 5 5 Galathowenia oculata 51 0.85 789 6 6 Pectinariidae (juv) 43 0.86 632 7 7 Chaetozone setosa 26 0.65 264 8 8 Minuspio cirrifera 12.5 0.42 217 9 14 Trichobranchus roseus 12 0.60 168 10 10 Scoloplos armiger 11.5 1.15 197 Adult Only Data Set 1 1 Pholoe assimilis 97 0.97 2,112 2 2 Paramphinome jeffreysii 91 1.01 1,909 3 3 Galathowenia oculata 71 0.98 789 4 4 Chaetozone setosa 44.5 0.64 264 5 5 Minuspio cirrifera 32 0.53 217 6 7 Scoloplos armiger 23.5 0.47 197 7 11 Trichobranchus roseus 21 0.53 168 8 6 Levinsenia gracills 20.5 0.68 199 9 8 Philin 19 0.95 189 10 10 Amphiura filiformis 18 1.80 176 Source: GEL 2011 The survey found that overall; the fauna was generally uniform and moderately diverse, with some patchy low and high abundance across the survey area. The community was typical of sandy North Sea sediments, with an abundance of juvenile echinoderms due to the seasonality of the survey. Although much of the community variation appears to be related to subtle changes in the sediment particle size, there was a slight trend in the faunal community that might be attributed to elevated lead and tin concentrations in the survey area (GEL 2011). One individual of A. islandica, a species listed by OSPAR (2008) as under threat and/or in decline in the North Sea, was identified at Station ENV9. There was no other evidence of threatened and/or declining species listed under OSPAR (2008) or UKBAP (2011). There was no indication from the acoustic data, seabed imagery or seabed sampling within the area surveyed of any Annex 1 habitats protected under the UK’s Offshore Marine Conservation (Natural Habitats, &c.) (Amendment) Regulations 2010, which implement the EC Habitats Directive 92/43/EEC (GEL 2011). The photographs below (Figure 8-1) are representational of the seabed conditions observed during the baseline survey.

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Figure 8-1: Seabed photographs of the Galia development area

The proposed development is located within an area of previous drilling activity. The development area is sufficiently homogenous that any localised losses are unlikely to affect the integrity of the community as a whole. In general, recolonisation is expected to occur quickly with the initial appearance of opportunistic species such as polychaetes of the spionid family; followed by a progression over time to a more stable and diverse community, better representing the current conditions.

8.2.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect benthic communities are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 8-4: Benthic communities – potential impact identification Project Activity Aspect Potential Impact Construction Physical damage to Physical presence and Anchoring individuals movement of vessels Smothering Physical damage to Discharge of cuttings individuals Smothering Drilling of wells Discharge of chemicals (including WBM) Discharge of reservoir Potential toxic effects hydrocarbons Discharge of chemicals Physical presence of subsea Habitat loss Installation of infrastructure and flowlines Physical damage to flowlines Trenching and backfill individuals Concrete mattressing and rock Smothering placement Habitat creation Production Operation and Discharge of produced water Potential toxic effects maintenance of FPSO Discharge of chemicals Accidental Events Overboard loss of Physical damage to Dropped objects equipment or waste individuals Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical spill Smothering release (1-10 tonnes) (including OBMs) Potential toxic effects Chemical / hydrocarbon release (>10 tonnes)

8.2.4 Control & Mitigation Measures

Measures outlined in Sections 7.3.4 and 7.4.4 adopted to reduce and/or eliminate the toxic impacts of the development on water quality and the footprint of the development on the seabed will also mitigate the potential impacts on the benthic community. These are not repeated here but are listed in the previous sections and summarised in Table 11-2 and in Sections F of Appendix A2 and A3 and Section D of Appendix A4.

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8.2.5 Residual Impact Significance Assessment

8.2.5.1 Physical disturbance

The main impact of construction activities on benthic communities results from physical disturbance to the habitat either as a result of direct removal of the habitat or smothering of individuals and/or the habitat. As discussed in Section 7.3.5.2, a maximum of 0.33km2 of seabed will be disturbed by construction activities. In all instances the direct result will be mortality of flora and fauna within the impact footprint. Individuals on the periphery of the project footprint and to some extent within the direct footprint may show some tolerance to disturbance particularly if the disturbance is short-term in nature. As disturbance from the majority of project activities will cease within a few days, or at most within a few months, this will allow for recovery and recolonisation of disturbed areas to commence almost immediately.

The placement of concrete mattresses on the seabed will smother individuals within the immediate footprint of the structures. Sedentary species will be particularly vulnerable to burial as they are unable to avoid such disturbances. The area of hard substrate is expected to attract colonisation of certain species that require hard substrate for anchoring points, but it may take longer to establish a community due to the limited larval supplies in the predominantly sandy surrounding areas. However, the area affected is extremely small (0.0027km2) in comparison to the considerable extent of sandy sediments in the wider region.

8.3 FISH AND SHELLFISH

8.3.1 Baseline Data Sources

The data sources used to inform this section are:

Catch statistics, provided by the Marine Management Organisation from the iFish2 UK wide database (2004 to 2010)

Spawning and nursery grounds of selected fish species in UK waters (Ellis et al. 2012) 8.3.2 Existing Baseline

Approximately 230 species of fish inhabit the North Sea. Analysis of fisheries statistics from the Marine Management Organisation (MMO) provides a useful indication of the type of species present in the development area, although not a definitive, as this data is not collected to provide an account of the community structure of fish and shellfish. However, it serves as a useful indicator, as many of the species found in the North Sea are commercially exploitable. The North Sea has been divided into a number of rectangles by the International Council for the Exploration of the Seas (ICES), which are used to report fisheries statistics. The Galia development lies in ICES rectangle 41F2, and catch statistics for the period 2004 to 2010 were obtained for this area to inform the EIA. The most commonly caught species in the area are given in Table 8-5 below. Approximately 38 species are caught within this ICES rectangle, with landings

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between 2004 and 2010 being dominated by herring (Clupea harengus). Haddock (Melanogrammus aeglefinus), lemon sole (Microstomus kitt) and plaice (Pleuronectes platessa) were also caught in significant numbers. Table 8-5: Commonly caught species in ICES rectangle 41F2 Demersal Pelagic Crustaceans Haddock Herring Norwegian lobster (Nephrops) Lemon Sole Mackerel Scallops Plaice Source: MMO (2011)

Fisheries sensitivity maps (Ellis et al. 2012) have been used to identify the spawning (location where eggs are laid) and nursery grounds (location where juveniles are common) for commercial fish species in the vicinity of the development area. Information on spawning and nursery periods for each species is detailed in Table 9-6 below. Spawning in the region occurs mainly between November and June, with peaks in January, February and March. Juveniles from the species in Table 8-6 may be present in the region all year round. Table 8-6: Key sensitive periods for fish spawning and nursery Species Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Anglerfish N N N N N N N N Blue N N N N N whiting Cod SN S*N S*N SN N N Hake N N N N N N N N Herring N (no seasonal data) Ling N N N N N N Mackerel N N N N N N Plaice S*N S*N SN N N SN Sandeels SN SN N N SN SN Spotted N N N N N ray Spurdog N - Viviparous, gravid females can be found at all times Whiting SN SN SN SN SN N N Key: S = Spawning, S* = Peak spawning, N = Nursery and blank = no sensitivity. Source: Ellis et al. (2012)

8.3.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect fish and shellfish are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 8-7: Fish and shellfish – potential impact identification Project Activity Aspect Potential Impact Construction Physical damage to individuals, Anchoring collision risk, smothering Organic enrichment leading to raised Discharge of sewage, grey water, food biological oxygen demand. May increase Physical presence and waste and drainage water plankton & fish populations changing movement of vessels balance of food chain Disturbance causing avoidance of Subsea noise spawning & nursery grounds Physical damage to individuals Loss of spawning & nursery ground Discharge of cuttings effecting stock viability Drilling of wells Physical damage to individuals Discharge of chemicals (including WBM) Discharge of reservoir hydrocarbons Potential toxic effects Discharge of chemicals

Physical presence of subsea infrastructure and flowlines Habitat loss Installation of flowlines Physical damage to individuals Trenching and backfill Smothering Habitat creation Concrete mattressing and rock placement Production Discharge of produced water

Operation and Potential toxic effects maintenance of FPSO Discharge of chemicals

Increased movement of export tanker and Subsea noise Localised disturbance supply vessels

Accidental Events Overboard loss of Dropped objects Physical damage to individuals equipment or waste Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical spill Smothering release (1-10 tonnes) (including OBMs) Potential toxic effects Chemical / hydrocarbon release (>10 tonnes) 8.3.4 Control & Mitigation Measures

Potential impacts that require mitigation generally fall into two categories: those that could have toxic effects and those that disturb the seabed causing loss of habitat and spawning/nursery grounds. Measures to mitigate deterioration in

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water quality and toxic effects of chemicals have previously been outlined in Section 7.3.4, whilst measures to minimise physical disturbance to the seabed are discussed in Section 7.4.4. They have not been repeated in full here but are summarised in Table 11-2 and are provided in Sections G of Appendix A.

8.3.5 Residual Impact Significance Assessment

8.3.5.1 Habitat disturbance and noise

As discussed in Section 5.5.3, a maximum of 0.33km2 of seabed will be disturbed by construction activities. This has the potential to disturb the spawning grounds for demersal species such as haddock and whiting. The main disturbance (flowline installation) will take place during the first and second quarter 2013. Although disturbed, the composition of sediments is unlikely to significantly change and the habitat should still be suitable for spawning once construction has ceased. As the spawning area for the demersal species encompasses a large area of the North Sea, a small disruption at the development site is not anticipated to affect populations or stock viability. The placement of concrete mattress and other subsea infrastructure, will create new habitat for those benthic species that require hard substrate for anchoring. This could lead to settlement of new species and the potential for a localised change in marine ecology (increased localised biodiversity). This could in turn lead to more food sources for fish and shellfish species. As the majority of the noise generated by offshore oil installations is low frequency (<1kHz), any impact is likely to be minimal and no piling activities will be carried out at Galia.

8.3.5.2 Toxic effects

The most significant sources of potential toxic effects are identified as a major spill (e.g. greater than 10 tonnes) either during construction or due to a loss of containment during production. The likelihood of these events has been addressed in Section 6.2. In fish life cycles the egg and juvenile stages are the most vulnerable to toxicity in the water column, as adult fish are highly mobile and generally able to avoid localised polluted areas. Localised fatalities would occur as the pipeline breaches, but fish are likely to avoid the area if the situation persists, and any effects are unlikely to be felt on a population level. As discussed in Section 8.3.2 the Galia development area lies within the spawning areas for mackerel, lemon sole and sprat and within the nursery areas for haddock and whiting (Coull et al. 1998). However, the spawning/nursery grounds span large areas of the North Sea such that relatively localised impacts are unlikely to lead to long term changes to the population as a whole. In general, lighter refined petroleum products such as diesel and gasoline are more likely to mix in the water column and are therefore more toxic to marine life. However, they tend to evaporate quickly (as demonstrated in the oil spill modelling) and do not persist long in the environment. Although heavier residual oils tend to have specific gravities greater than sea water, causing them to sink once spilled, the reservoir oil at Galia is light crude which is

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unlikely to sink. A major hydrocarbon spill has therefore been assessed as having the potential for an impact of minor significance on fish and shellfish.

8.4 SEABIRDS

8.4.1 Baseline Data Sources

The principal data sources used to inform this section were:

Atlas of seabird distribution in the north-west European waters (Stone et al. 1995)

Seabird vulnerability in UK waters: block specific vulnerability (Skov et al. 1999)

Strategic Environmental Assessment of the Mature Areas of the North Sea (SEA2) (DTI 2001a) 8.4.2 Existing Baseline

The CNS is an important area for guillemots (Uria aalge), fulmars (Fulmarus glacialis), gannets (Sula bassana), kittiwakes (Rissa tridactyla), herring gulls (Larus argentatus), great black-backed gulls (Larus marinus), and little auks (Alle alle). In July, large concentrations of guillemots occur in the CNS, with a gradual movement towards eastern Scotland and north-east England through August and September, and onwards dispersal to a more widespread distribution in the Southern North Sea in winter (DTI 2001a). The density and distribution of seabirds varies throughout the year. The breeding season extends from May to June with birds congregating at coastal colonies from March onwards. During this time seabirds remain close to their colonies, and numbers of birds at sea decrease. By late summer many species, such as guillemots and razorbills, leave their colonies and undergo a post-breed moult during which they are flightless. Significant concentrations of moulting adults and associated fledgling juveniles congregate on the water. Following the autumnal moult seabirds begin to disperse to their wintering grounds (Stone et al. 1995). Skov et al. (1995) detailed an Important Bird Areas (IBA) programme which identifies a network of sites, at a geographic scale, which are critical for the long term viability of bird populations. Although the areas are not afforded any statutory protection, they do serve as a useful indication of which areas of UK waters are of particular importance to seabirds. The Galia development is located approximately 41km north east of IBA 9 (Northeast Bank) (Figure 8-2). The IBA is an important breeding and feeding area for many vulnerable bird species including fulmars, gannets and the great skua (Catharacta skua) As specified by the JNCC (1999), seabird vulnerability refers to susceptibility to surface pollutants, specifically hydrocarbons, following breeding and during moulting at sea. Seabirds are also vulnerable to oil spills during the winter months when they congregate in large flocks on the water. The details of seabird vulnerability in Blocks 30/24, within which the Galia development lies, and the surrounding blocks are given in Table 8-8. The development block is shown in bold. Information on seabird vulnerability is also shown in Figure 8-2.

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.! ^_ .!XW 56°0'N 56°0'N 55°30'N 55°30'N

1°0'E 1°30'E 2°0'E 2°30'E 3°0'E 3°30'E

Legend Median Line Galia Field Development Environmental Statement Land Figure 8-2: Environmental overview UKCS Block

Date Friday, March 2, 2012 13:15:18 Galia Well ^_ Projection ED 1950 UTM Zone 31N XW EnQuest Producer FPSO Spheroid International 1924 .! Alma Production Centre Datum D European 1950 Alma Water Injection Centre .! Data Source EnQuest, JNCC, UKDeal, Skov et al 1998 Galia Production Flowline Alma Production Flowline File Reference J:\P1459\Mxd\Environmental Statement\Galia ES\ Alma Water-Injection Flowline Figure 8-2 Environmental Overview.mxd

! ! Produced By Emma White Net Gain draft MCZ

! ! ! Checked Dogger Bank cSAC ! Reviewed By Louise Mann

Northeast Bank IBA Annual Seabird Vulnerability 1 - Very High 2 - High 3 - Moderate km © Metoc Ltd, 2011. 4 - Low NOTE: Not to be used for navigation 05 10 20 30 40 50 All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Table 8-8: Seabird vulnerability in the vicinity of Block 30/24 Block Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 30/18 2 4 4 4 4 4 4 4 4 3 3 3 30/19 3 4 4 4 4 4 4 4 4 3 4 3 30/20 2 4 4 4 4 4 4 4 4 2 3 3 30/23 2 2 3 4 4 4 4 4 4 2 3 3 30/24 2 4 3 4 4 4 4 4 4 2 3 3 30/25 2 4 3 4 4 4 4 4 4 2 3 3 30/28 2 2 3 4 4 4 4 4 4 2 3 4 30/29 2 4 3 4 4 4 4 4 4 2 3 4 30/30 2 4 3 4 4 4 4 4 4 2 3 4 31/21 2 4 4 4 4 4 4 4 2 3 31/26 2 4 4 4 4 4 4 4 2 4

Key 1 = Very High 2 = High 3 = Moderate 4 = Low Blank = No data Source: JNCC (1999)

The data in Table 8-8 suggests seabird vulnerability is generally low for most of the year, with a significant increase in vulnerability in January and October. This increase in vulnerability is possibly the result of the arrival of over-wintering birds.

8.4.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect seabirds are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 8-9: Seabirds – potential impact identification Project Activity Aspect Potential Impact Construction Localised disturbance of Physical presence and Increased vessel activity in region seabirds from the sea movement of vessels surface Discharge of chemicals (including Drilling of wells WBM) Potential toxic effect Discharge of reservoir hydrocarbons Installation of flowlines Discharge of chemicals Production Operation and maintenance of Discharge of produced water Potential toxic effect FPSO Discharge of chemicals Increased movement of export Localised disturbance of Subsea noise tanker and supply vessels seabirds Accidental Events Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical spill Smothering release (1-10 tonnes) (including OBMs) Potential toxic effects Chemical / hydrocarbon release (> 10 tonnes) 8.4.4 Control & Mitigation Measures

General mitigation measures to minimise the toxic potential of chemicals and thus reduce exposure concentrations for seabirds will be in place, as discussed in detail in Section 7.3.4 and Appendix A. Accidental spills of hydrocarbons present the largest potential impact on seabirds. The mitigation measures to prevent crude oil and diesel spills are discussed in more detail in Section 6.3.

8.4.5 Residual Impact Significance Assessment

Mitigation measures taken during construction and production phases have been assessed to reduce the impact on seabirds in the area. As such, none of these activities have been taken forward for residual impact significance assessment (see Sections H of Appendix A2 and A3).

8.4.5.1 Accidental events: spill of hydrocarbon >10 tonnes

There is potential for seabirds to be significantly affected by a large crude oil spill, either during construction or as a result of a loss of containment during production. The likelihood of these events was addressed in Section 6.2. A diesel spill will rapidly evaporate on release and will naturally disperse in the high energy offshore environment. Modelling, undertaken for the Alma ES and discussed in Section 6.4.2 and Appendix B, indicates that a diesel spill of 5,830m3 i.e., from a combined loss of inventory from the FPSO and export tanker, will naturally disperse and evaporate within 10 hours. As such, it is not

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considered that diesel will pose a significant threat to seabirds given the large area over which the birds will be present. During construction, the loss of well control (blow out) could result in a spill of up to 1,992 tonnes (2,385m3) of crude oil per day. Over the 15 day period the modelling is run for this would result in a spill of 29873 tonnes (35,775m3) of crude oil. Modelling shows that in the event of a loss of well control, there is a 1% chance of oil beaching along the coastline of one or more of the countries bordering the North Sea. All modelling results are presented in Appendix B. Any spills of the magnitude modelled above are likely to significantly impact populations of seabirds. Seabirds that spend majority of the time on sea surface are most vulnerable as birds can be smothered by oil or their feathers can become contaminated with hydrocarbons, which in turn may be ingested. Seabird vulnerability to hydrocarbon pollution is highest in January and October. As the drilling rig will be on-site from January 2012 until December 2013 (Alma and Galia combined), there will be overlap with the sensitive periods for seabirds. In addition, the FPSO will offload crude oil every two weeks throughout the year and therefore at some point each year operations will overlap with the sensitive periods identified. In the event of a spill occurring, the required intervention response will be implemented to minimise the risk of smothering and species injury. It is highly unlikely that a spill of the magnitude discussed above will occur. Mitigation measures outlined in the OPEP and management controls to eliminate spills should prevent any sizeable spills. Given the likelihood of an impact occurring is unlikely the EIA concluded that residual significance of the impact is moderate.

8.5 MARINE MAMMALS

8.5.1 Baseline Data Sources

This section draws upon information from the following data sources:

Atlas of Cetacean distribution in northwest European waters (Reid et al. 2003)

Background Information on Marine Mammals Relevant to SEA2 (DTI 2001d).

Background information on marine mammals relevant to SEA 2 and 3 (DTI 2002)

The effects of seismic activity on marine mammals in UK waters (Stone 2003)

The protection of marine European Protected Species from injury and disturbance guidelines (JNCC 2010)

UK Offshore Energy Strategic Environmental Assessment. Environmental Report (DECC 2009) 8.5.2 Existing Baseline

Distribution of marine mammals in UK waters varies by species. For example some species are more frequently found on the continental shelf or in areas of

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deep water (e.g., white-beaked dolphin), whilst others are more commonly found in inshore waters (e.g., bottlenose dolphin). There are eight marine mammal species that occur regularly over large parts of the North Sea (DTI 2001d):

Harbour porpoise (Phocoena phocoena)

Bottlenose dolphin (Tursiops truncatus)

White-beaked dolphin (Lagenorhynchus albirostris)

Atlantic white-sided dolphin (Lagenorhynchus acutus)

Killer whale (Orcinus orca)

Minke whale (Balaenoptera acutorostrata)

Harbour seal (Phoca vitulina)

Grey seal (Halichoerus grypus) Cetaceans The CNS region is important for the three most abundant cetacean species in the North Sea: minke whale, harbour porpoise, and white-beaked dolphin. Current evidence suggests that the CNS is particularly important for the harbour porpoise. Densities are greatest in summer, north of 56ºN and between 1ºE and 3°E (DTI 2001d). This area includes the prospective field development location. Table 8-10 below details the cetacean sightings data in the vicinity of the Galia field. This data suggests that nine species are present within and adjacent to the field and that most sightings occur during the summer months (Reid et al. 2003). Table 8-10: Cetacean observations in the area of interest Species Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Minke Whale 2 2 2 2 3 3 3 3 2 2 3 3 Killer Whale 1 1 1 1 1 Harbour Porpoise 1 1 1 1 2 3 4 2 2 2 1 1 Risso's Dolphin 1 1 2 1 1 1 White Beaked Dolphin 1 2 1 1 4 2 4 3 3 3 3 1 White Sided Dolphin 1 1 1 3 2 4 Bottlenose Dolphin 1 1 1 1 1 1 3 2 1 1 1 1 Common Dolphin 2 2 Key: Blank cell: Little or no observational effort and/or unlikely to be present in CNS, 1: Recorded in CNS, 2: Recorded in blocks adjacent to area, 3: Recorded in development area, 4: Frequent in development area. Source: Reid et al. (2003)

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Table 8-11 presents abundance and density estimates for the five species identified as most frequently occurring in the development area (taken from Table 8-10). The conservation status of the species is also included. It is an offence under the Conservation (Natural Habitats etc.) Regulations 1994 (as amended) (HR) and the Offshore Marine Conservation (Natural Habitats, etc.) Regulations 2007 (as amended in 2010) (OMR) to deliberately capture, injure, kill or disturb any wild animal of an EPS (European Protected Species). All cetacean species are designated as EPS. Disturbance of animals includes, in particular, any disturbance which is likely to: a) Impair their ability - (i) to survive, to breed or reproduce, or to rear or nurture their young; or (ii) in the case of animals of a hibernating or migratory species, to hibernate or migrate; or b) Affect significantly the local distribution or abundance of the species to which they belong. Table 8-11: Cetacean population estimates and conservation status Species Natural UK SNS & southern CNS Species Significant Range Population Population Density Favourable Group 2 (km ) Estimate Estimate1 (animals/km2) Conservation (animals) Status Harbour Unknown 328,200 129,000 (39%) 0.46 Favourable 4,600 porpoise White-beaked Unknown 22,400 493 (2%) 0.0031 Favourable 450 dolphin Minke whale 759,000 13,800 4,700 (34%) 0.017 Favourable 330 White-sided Unknown 27,300 405 (1.5%) 0.0026 Unknown 100 dolphin Bottlenose 759,000 8,000 395 (5%) 0.0032 Favourable 160 dolphin Note 1: Percentage of UK population presented in brackets. Source: JNCC (2009), SCANS-II (2008), DECC (2009b)

Cetaceans use sound to communicate, socially interact, and in some cases navigate using echolocation. There are two principal effects to exposure to noise; physical injury or physiological effects and effects associated with behavioural disturbances. Anthropogenic sources of noise therefore have the potential to interfere with their natural functions, and if the cetacean is within close proximity to loud noises, this can have the potential to cause physical injury (Stone 2003). Harbour porpoise, white-beaked dolphins, minke whales and killer whales are typically seen in pods of less than ten animals. Activities that would disturb a significant group of these animals would have considerable duration (JNCC 2010). Atlantic white-sided dolphin, Risso’s dolphin and pilot whales tend to form pods of greater than twenty animals. Pinnipeds The two most common species of pinniped (seal) in the North Sea are the harbour (or common) (Phoca vitulina) and grey seals (Halichoerus grypus).

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The harbour (common) seal is one of the most widespread pinniped species and has a practically circumpolar distribution in the Northern Hemisphere. The distribution of harbour seals at sea is limited by the need to return to land periodically. Until recently, data showed they were unlikely to be found more than 60km from the coast, although recent telemetry studies show a wider distribution across the North Sea (DTI 2002). Although long distance movements are possible, this is usually to other haul out sites and maps indicate that their distribution is predominately coastal (DECC 2009). Given that Galia is 280km from the UK coastline, it is unlikely that the range would extend that far. Grey seals have a wide distribution across the north-western Atlantic, Baltic and north east Atlantic seas. UK populations are estimated to be approximately 130,000 individuals with a growth rate of 2.5% (DECC 2009). Populations in the North Sea account for approximately 50% (~70,000 individuals) of the northeast Atlantic population. Grey seals are mainly distributed around and between haul- out sites and foraging areas and are more commonly seen in the CNS and NNS than in the SNS (DECC 2009). Pinnipeds are particularly sensitive between October and January when they are on land pupping and again between February and March during their annual moult. It is possible that both species may be observed in the development area although it is unlikely given the distance offshore.

8.5.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect marine mammals are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 8-12: Marine mammals – potential impact identification Project Activity Aspect Potential Impact Construction Can cause physical injury Subsea noise or disturbance Physical presence and Anchoring Collision risk movement of vessels Feeding impairment due to Discharge of sewage, grey water, organic enrichment effecting food waste and drainage water balance of food chain Discharge of chemicals (including WBM) Potential toxic effect Drilling of wells Discharge of reservoir hydrocarbons Localised disturbance of Subsea noise marine mammals Installation of flowlines Discharge of chemicals Potential toxic effect Production Operation and maintenance of Discharge of produced water Potential toxic effect FPSO Discharge of chemicals Physical presence and Localised disturbance of movement of export tanker Subsea noise marine mammals and supply vessels Accidental Events Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon Diesel, crude or chemical spill Potential toxic effect release (1-10 tonnes) (including OBMs) Chemical / hydrocarbon release (>10 tonnes) 8.5.4 Control & Mitigation Measures

General mitigation measures to minimise the toxic potential of chemicals and thus reduce exposure concentrations for marine mammals will be in place, as summarised in Table 11-2 and detailed in Sections I of Appendix A2 and A3 and Section G of Appendix A4. Releases of hydrocarbons will be mitigated through a three stage process: prevention, control and remediation. This is discussed in detail in Section 8.4.4 and has not been repeated here.

8.5.5 Residual Impact Significance Assessment

8.5.5.1 Subsea noise

During construction and production, a range of activities will generate low levels of underwater noise consistent with a development of this size. These include: flowline laying and trenching, subsea installation, subsea monitoring and repair, vessel manoeuvring and drilling (see Sections 5.2 and 5.3). The majority of the

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noise sources are typical of construction activities associated with a small - to medium-sized development and are generally below 180dB. However, it is possible that background subsea noise generated by construction vessels and drilling may be audible to marine mammals within 1km of the source of sound. Subsea noise can affect marine mammals in three ways: blast impact, lung/organ resonance and hearing impairment. Of these three mechanisms, the first two have been discounted on the basis that no piling activities will be carried out at Galia. The potential for hearing impediment from noise is dependent on the animal’s hearing ability across the range of source frequencies. The JNCC (2009) suggested risk assessment approach is provided as Figures D-1 and D-2 in Appendix D.

8.5.5.2 Accidental events: spill of hydrocarbon >10 tonnes

Although the region surrounding the Galia development is not considered to be particularly important for marine mammals (Table 8-10), should a major release of crude oil occur, there is the potential that individuals could be affected. In addition should any oil reach the shoreline, haul out sites for pinnipeds may be impacted. The likelihood of these events was addressed in Section 6.2. A diesel spill will rapidly evaporate on release and will naturally disperse in the high energy offshore environment. Modelling, undertaken for the Alma ES and discussed in Section 6.3.2 and Appendix B, indicates that a diesel spill of 5,830m3 i.e., from a combined loss of inventory from the FPSO and export tanker, will naturally disperse and evaporate within 10 hours. As such, it is not considered that diesel will pose a significant threat to marine mammals. During construction, the loss of well control (blow out) would result in a spill of 1,992 tonnes (2,385m3) of crude oil per day. Over the 15 day period the modelling is run for this would result in a spill of 29873 tonnes (35,775m3) of crude oil. Modelling shows a 1% chance of oil beaching along the coastline of one or more of the countries bordering the North Sea. All modelling results are presented in Appendix B. Cetaceans have smooth hairless skins over a thick layer of insulating blubber, so oil is unlikely to adhere persistently or cause a breakdown in insulation. Marine mammals must surface to breathe and they may inhale vapours given off the spilt oil and their eyes may be vulnerable to major pollution. Indirect effects may also be caused through contamination and depletion of food resources. Due to the transient nature of cetaceans, it is likely that individuals not in the immediate area of the spill when it occurs will avoid the area and it is possible that the number of individuals affected could be small. However, if a substantial number of a population where affected there could be knock on effects to breeding and the long-term viability of the population. Recovery rates of land based marine mammals such as seals could be longer particularly if a spill affected a breeding season.

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8.6 PROTECTED SITES AND SPECIES

8.6.1 Baseline Data Sources

The main data sources used were:

Gardline Environmental (2011). Galia Sites and Pipeline Route Surveys UKCS 30/24 and 30/25: Environmental Baseline Report. Ref 8826.5

JNCC website www.jncc.gov.uk

Natura in UK Offshore waters: Advice to support the implementation of the EC Habitats and Birds (Johnston et al 2004) 8.6.2 Existing Baseline

There are a number of protected areas (designated under both UK and International legislation) concerned with the marine and coastal environment. The main designations are: special areas of conservation (SAC); special protection areas (SPAs), RAMSAR sites; and sites of special scientific interest (SSSI). The EC Habitats Directive requires member states to designate Special Areas of Conversation (SACs) for the protection of a number of habitats, listed under Annex I, and species listed under Annex II, of the Directive. The main aim of the Directive is to promote the maintenance of biodiversity by requiring member states to take measures to maintain or restore natural habitats and wild species at a favourable conservation status (JNCC 2010). Each member state is required to propose a national list of sites for selection as SAC. The habitats and species in the Directive include examples of both that are entirely marine and four habitats and four species present in UK waters away from the coast (JNCC 2012). There are currently 96 SACs with marine components, covering 4.8% of the UK sea area. 10 of these SACs are completely in offshore waters and there are two sites which straddle inshore and offshore waters (JNCC 2012). Twelve marine sites have been submitted by the UK to the European Commission and are currently candidate SAC (cSAC). All these sites have now been approved by the EC as Sites of Community Importance (SCI) and await formal designation as SAC by the UK Government. A further eight sites have had Cabinet Committee approval to go out to formal public consultation and are designated as possible SAC (pSAC) (JNCC 2012). No protected areas occur within 40km of the development. The closest protected site to the field development is the Dogger Bank candidate SAC (cSAC), which lies approximately 78km south of Galia (Figure 8-2). The site has been formally recommended to the UK Government by the JNCC and has been submitted to be approved by the European Commission for designation as a full SAC. The cSAC supports communities typical of sandy sediments, characterised by polychaete worms, amphipods and small clams within the sediments and hermit crabs, flatfish and starfish on the seabed. Sandeels are abundant on the flanks of the bank and provide a food resource for seabirds, cetaceans and other commercial fish species, such as cod. The Dogger Bank region is an important location for the North Sea harbour porpoise population and as such they are included as a qualifying feature. Grey and common seals

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are known to visit the bank and are included as non-qualifying features at the site (JNCC 2011). The Galia site survey data was reviewed to assess the occurrence of habitat types listed on Annex I of the Habitats Directive. The four Annex I habitat types known to occur in UK offshore waters are:

Reefs (stony and biogenic)

Sandbanks which are slightly covered by seawater at all times

Submarine structures made by leaking gases

Submerged or partially submerged sea caves One individual of Arctica islandica was identified at Station ENV9; A. islandica is listed by OSPAR (2008) as a species under threat and/or in decline in the North Sea. At all other stations no habitats or species of conservation significance under the UK’s Offshore Marine Conservation (Natural Habitats, &c) (Amendment) Regulations 2010, which implement the requirements of the EC Habitats Directive, were observed (GEL 2011). Annex II Species Of 788 European species listed in Annex II of the EC Habitats Directive, over twenty species are known to occur, or could potentially occur, in UK offshore waters. These are:

Cetacea - Dolphins, porpoises and whales (all species)

Sturgeon (Acipenser oxyrinchus)

Marine turtles (all species)

Barbel (Barbus barbus)

Grayling (Thymallus thymallus)

Atlantic Salmon (Salmo salar)

Seals – Common (Phoca vitulina) and Grey (Halichoerus grypus)

Shad - Allis (Alosa alosa) and Twaite (Alosa fallax) Of the Annex II species listed above, five species of cetacea and two species of pinniped are found within the vicinity of the project area. Their distribution and sensitivity to the project are previously discussed in detail in Section 8.5. Marine Protected Areas There are currently four regional projects in progress to identify potential marine conservation zones (MCZ) around the UK. Finding Sanctuary (south-west), Irish Sea Conservation Zones (Irish Sea), Balanced Seas (south-east) and Net Gain (North Sea)2. The North Sea Marine Conservation Zones Project (Net Gain) has identified a potential Marine Conservation Zone approximately 3.3km west of Galia (Figure 8-2). This site has been recommended as a representative example of subtidal coarse sediment and sand broad scale habitats; the ‘subtidal sands and gravels’ Habitat of Conservation importance and ocean quahog (Arctica islandica) which are a Species of Conservation importance (Net Gain 2011).

2 Further details on the regional MCZs can be found on the JNCC website http://jncc.defra.gov.uk/page-2409

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8.6.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect protected sites and species are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 8-13: Protected sites and species – potential impact identification Project Activity Aspect Potential Impact Construction Could affect integrity of protected Anchoring site Physical presence and Can cause physical injury or Subsea noise movement of vessels disturbance to protected species Discharge of sewage, grey water, Potential toxic effects on protected food waste and drainage water species Can cause physical injury or Subsea noise disturbance to protected species Could affect integrity of protected Discharge of cuttings Drilling of wells site Discharge of chemicals (including WBM) Potential toxic effect on protected Discharge of reservoir hydrocarbons species Discharge of chemicals Physical presence of subsea Installation of flowlines infrastructure and flowlines Could affect integrity of protected Concrete mattressing and rock site protection Production Physical presence, Discharge of produced water Potential toxic effects through operation and bioaccumulation of chemicals and maintenance of FPSO Discharge of chemicals hydrocarbons in food chain Physical presence and increased movement of Can cause physical injury or Subsea noise export tanker and disturbance to protected species supply vessels Accidental Events Overboard loss of Could affect the integrity of a Dropped objects equipment or waste protected site Chemical / hydrocarbon release (< 1 tonne) Smothering of protected species Chemical / hydrocarbon Diesel, crude or chemical spill Potential affects on integrity of a release (1-10 tonnes) (including OBMs) protected site Chemical /

hydrocarbon release (>10 tonnes) In general, these aspects have the potential to adversely affect protected sites and species, through risk of collision, disturbance and through the deterioration

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of individuals, generally on a site specific basis (i.e., effects restricted to the project area). Some of the accidental events assessed potentially have a much wider area of impact e.g., the local or wider region. The sensitivity of the impacts varies from low to medium depending on the activity but all impacts are restricted to short-term effects.

8.6.4 Control & Mitigation Measures

The potential impacts on protected sites and species are the same as on the baseline physical and biological conditions of the project area (noting potential for national or international consequences). As such, measures to actively mitigate impacts on protected sites and species are similar to those employed to mitigate impacts on the individual components of the environment which the designation protects. These are discussed in detail in relevant sections of this ES e.g., seabed conditions (Section 7.4.4), benthic communities (Section 8.2.4), seabirds (Section 8.4.4) and marine mammals (Section 8.5.4).

8.6.5 Residual Impact Significance Assessment

8.6.5.1 Physical disturbance of a protected feature

The Galia development does not lie within a protected area. There are no protected sites within 40km of the development area; the closest protected site is the Dogger Bank cSAC which lies approximately 78km south of Galia. Due to the distance involved, the project footprint is not expected to overlap with the site. Therefore, the integrity of any protected site is not anticipated to be affected by the Galia development. The impact on protected species of marine mammals and seabirds are discussed in Sections 8.4.5 and 8.5.5.

8.6.5.2 Accidental events: spill of hydrocarbon >10 tonnes

There is the potential that protected sites and species could be significantly affected if a large crude oil spill was to occur. The likelihood of major spills is addressed in Section 6.2. Although there are no designated protected sites within 40km of the Galia field, a major crude oil spill caused by a loss of containment due to collision (i.e., the FPSO and export tanker with each other) or a loss of well control have been modelled as the worst case scenarios and the modelling results are presented in Section 6.4 and Appendix B. Due to the transient nature of cetaceans, for which the Dogger Bank is notified, and the distance to the Dogger Bank cSAC (78km) it is likely that individuals not in the immediate area of the spill when it occurs will avoid the area and it is probable that the number of individuals affected could be small. There is a 1% chance that oil could beach along the coastline of one or more of the countries bordering the North Sea. As can been seen from Figure 9-3, there are numerous protected sites along the coastlines of those North Sea countries that could be affected. Should a spill occur that could potentially affect a protected area an intervention response would be required. It is highly unlikely that a spill of the magnitudes discussed above will occur. Mitigation measures outlined in the OPEP and management controls to eliminate spills should prevent any sizeable spills.

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Median Line Land

62°0'N Galia Well 62°0'N 62°0'N 62°0'N

Potenital beaching locations due to loss of containment from the Uisge Gorm FPSO Potenital beaching locations due to loss of well control at Galia

UK Protected Sites SAC dSAC 58°0'N 58°0'N cSAC 58°0'N 58°0'N pSAC SPA Ramsar

Non UK Protected Sites German Protected Sites Danish Protected Sites Dutch Protected Sites 54°0'N 54°0'N 54°0'N

54°0'N Norwegian Protected Sites

Date Thursday, October 27, 2011 17:29:58

Projection ED_1950_UTM_Zone_31N

Spheroid International_1924

Datum D_European_1950

Data Source UKDeal, MMO, OSR, WDPA, SNH, JNCC

50°0'N File Reference J:\P1459\Mxd\Environmental Statement\Galia ES\ 50°0'N Figure 8-3 Beaching locations & Protected sites.mxd 50°0'N 50°0'N Produced By Emma White Checked Reviewed By Louise Mann

© Metoc Ltd, 2011. 0°0' 4°0'E 8°0'E 055 110 220 330 440 0°0' 4°0'E 8°0'E Km All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

9 IMPACTS ON HUMAN ENVIRONMENT

This section describes the existing baseline human environment, the potential impacts arising from the Alma development project thereon, and their mitigation as appropriate. The section also qualifies the significance of any residual impacts as follows:

Commercial fishing (Section 9.1)

Shipping and navigation (Section 9.2)

Other marine users (Section 9.3)

Archaeology (Section 9.4) It follows the methodology set-out in Section 4.

9.1 COMMERCIAL FISHERIES

9.1.1 Baseline Data Sources

This section makes use of the following data sources:

MMO fisheries statistics from 2004 to 2010 (MMO 2011)

Fisheries Sensitivity Maps (Coull et al. 1998) 9.1.2 Existing Baseline

The North Sea is home to approximately 230 species of fish, thirteen of which are the main targets for commercial (direct human consumption) and industrial fisheries (where the catch is converted into fish meal and oil) (OSPAR Commission 2000). For the purposes of this EIA “commercial fishing” includes all fishing for commercial gain (i.e., commercial + industrial). Section 8.3 provides more information on the fish species present in the Galia development area. Major UK and international fishing fleets operate in the North Sea, producing more than 3 million tonnes per annum and contributing approximately 4% of the world’s fishery production (Coull et al., 1998). Fleets target both pelagic and demersal fish stocks, as well as significant shellfish stocks such as the commercially valuable Norway lobster (Nephrops). An assessment of the fishing industry in the region of the development has been derived from Marine Management Organisation (MMO) catch statistics for the period 2004 to 2010 (MMO 2011). Statistics were obtained for the ICES rectangle 41F2, a 30nm square area within which the Galia development area is located, and the surrounding rectangles. The data provides details on receiving port, species landed (live weight in tonnes) and value of species. The data considers all vessels using UK ports and UK vessels using foreign ports but does not take into account foreign vessels landing at foreign ports. The Galia development area is not considered to be a commercially important ground for pelagic and demersal species. Analysis of the statistics indicates that:

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Approximately 125 tonnes of fish and shellfish, worth approximately £115,703 are landed each year from ICES rectangle 41F2.

Overall catch (live weight tonnes) is dominated by the pelagic species herring (Clupea harengus) (427 tonnes in 6 years).

Herring, as well as the demersal species lemon sole (Microstomus kitt), and haddock (Melanogrammus aeglifinus) are the most commercially valuable species targeted in the region.

The shellfish fishery is of relatively low value (approximately £4,700 per year), with the majority of the catch represented by Norway lobster (Nephrops norvegicus), scallops and low value squid (Loligo vulgaris). An idea of the importance of commercial fishing in the immediate vicinity of Galia can be gained by comparing ICES rectangle 41F2 with those in the surrounding area (e.g., 40F1, 40F2, 41F1, 42F1 and 42F2). This comparison is tabulated in Table 9-1 below and illustrated in Figure 9-2. The table indicates that ICES rectangle 41F2 is the most productive and commercially valuable area for herring in the region, but that overall the commercial fishery is of moderate to low value in comparison to other adjacent areas. Table 9-1: Value (£) of landing for the Galia development area and surrounding region (2004 – 2010) ICES Rectangle Herring Lemon Sole Plaice Haddock Nephrops Total from Block 40F1 32,166 39,423 23,392 108,757 159,255 362,993 40F2 43,832 315,153 315,207 8,556 6,190 688,938 41F1 - 130,531 30,308 126,942 2,048,093 2,335,874 41F2 118,677 324,257 79,252 188,279 22,392 732,857 42F1 52,974 589,554 58,118 239,023 2,607,962 3,547,631 42F2 - 295,900 45,220 198,713 9,645 549,478 Grand total (2004 – 2010) from all rectangles 247,649 1,694,818 551,497 870,270 4,853,537 8,217,771 Catch from 41F2 as a percentage of total species specific catch from the area 47.92% 19.13% 14.37% 21.63% 0.46% 8.92% Average annual catch from 41F2 19,780 54,043 13,209 31,380 3,732 122,143 Source: MMO (2011) The relative value of the fisheries within ICES rectangle 41F2, when compared to the rest of the North Sea, is low (Coull et al. 1998). Fishing activity in the vicinity of Galia is generally low at the beginning of the year (January to March). This rises to a peak in August before falling off again towards the end of the year with a small peak in December (Figure 9-1). The bulk of the catch from ICES rectangle 41F2 (live weight tonnes) in 2004-2010 was landed at either Scheveningen in The Netherlands (374 tonnes) or Peterhead, Aberdeenshire (303 tonnes). A total of approximately 66 tonnes was also landed in Eyemouth, Berwickshire during this 6 year period.

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Figure 9-1: Seasonal variation in fishing activity (2004-2010)

Source: MMO (2011)

The DECC Online Maritime Data GIS system (Maritime Data 2011) indicates that a moderate number of fishing vessels are also active in the area. The development area is within an area of moderate fishing effort (based on days fished). Figure 9-2 shows the average annual catch (tonnes) and the average annual value of catch (£) in the Galia development area and surrounding region for the six year period 2004 – 2010.

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX 117 02/05/2012 1°0'E 2°0'E 3°0'E 1°0'E 2°0'E 3°0'E Galia Field Development Environmental Statement Figure 9-2: Average annual catch and value for Galia (2004-2009) . .. Legend

Median Line UKCS Block

^_ Galia Well 57°0'N

57°0'N XW

57°0'N EnQuest Producer FPSO 57°0'N .! Alma Production Centre

.! Alma Water Injection Centre Value (£) Live weight (tonnes) 0-50,000 0-50 50,000-100,000 50-100 100,000-200,000 100-200 200,000-300,000 200-250 300,000+

.! .! ^_.!XW ^_.!XW 56°0'N 56°0'N 56°0'N 56°0'N

NOTE: Not to be used for navigation

Date Friday, March 2, 2012 13:18:21

Projection ED_1950_UTM_Zone_31N

Spheroid International_1924

Datum D_European_1950

Data Source UKDeal, MMO

File Reference J:\P1459\Mxd\Environmental Statement\Galia ES\ Figure 9-2 Commercial Fisheries.mxd

Produced By Emma White Checked Reviewed By Louise Mann 55°0'N 55°0'N 55°0'N 05 10 20 30 40 © Metoc Ltd, 2011. 1°0'E 2°0'E 3°0'E 1°0'E 2°0'E 3°0'E Km All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

9.1.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect commercial fisheries are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 9-2: Commercial fishing – potential impact identification Project Activity Aspect Potential Impact Construction Increased vessel activity in Exclusion from fishing region grounds Physical presence and Exclusion zones Potential collision risk movement of vessels Anchor mounds could Anchoring snag fishing gear Cuttings pile could snag Discharge of cuttings Drilling of wells fishing gear Production Increased movement of Increased vessel activity in export tanker, support region Potential collision risk and supply vessels Presence of subsea Physical presence of subsea Could snag fishing gear infrastructure infrastructure and flowlines Accidental Events Overboard loss of Dropped objects Could snag fishing gear equipment or waste Chemical / hydrocarbon release (< 1 tonne) Potential decrease in Chemical / hydrocarbon Diesel, crude or chemical catch if stocks affected release (1-10 tonnes) spill (including OBMs) Damage to boats and Chemical / hydrocarbon gear release (>10 tonnes)

The EIA concluded that the majority of activities have the potential to impact commercial fisheries. Typically, impacts are of low significance, with a site- specific to low spatial extent. The likelihood, severity and significance of the impacts have been assessed in Sections K of Appendices A2 and A3 and Section I of Appendix A4.

9.1.4 Control & Mitigation Measures

Potential impacts requiring mitigation fall into two main categories:

Those that could impact directly on fishing (e.g., exclusion zones, hazards which could snag nets)

Those that affect the fish stocks.

Measures to mitigate the impact on fish species (through reduced water quality and toxic effects of chemicals) have been previously outlined in Section 8.3.4. Measures relating to minimising the seabed footprint are outlined in Section 7.4.4 and have not been repeated

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here. They have not been repeated in full here but are summarised in Table 11-2 and provided in Appendix A. The measures of direct relevance to commercial fisheries are detailed below:

To minimise snagging risks to fishing gear, a debris clearance survey will be conducted at the end of the construction phase and any significant objects will be removed. If the object cannot be retrieved a PON2 will be submitted to the DECC.

To minimise collision risks, a 500m safety exclusion zone around the drilling rig will be enforced. The drilling rig and construction vessels will be appropriately lit, sound warnings will be broadcast in poor visibility and all vessels will comply with IMO standards.

Via the Kingfisher fortnightly bulletins, Notices to Mariners and, where appropriate, VHF radio broadcasts users of the sea will be notified of:

The presence and intended movements of construction vessels

The presence of exclusion zones

The presence of new structures on the seabed and mattressed areas of seabed

The new wellhead will be within a 500m safety exclusion zone. However, the wellhead is designed to be fishing friendly to designs approved by the Scottish Fishermen’s Federation (SFF).

Field construction and operation vessels movements will be minimised. 9.1.5 Residual Impact Significance Assessment

9.1.5.1 Exclusion zones

A permanent 500m radius safety exclusion zones will be established around the Galia well head. The safety zone will be enforced by a guard vessel. There is potential for fishing vessels to be displaced from their fishing grounds due to the presence of the new zone. Fishing activity in the region of Galia is moderate (based on days fished data, see above). However, as the exclusion area is small in comparison to the wider ICES Block (0.79m2 in 3,086km2), it is unlikely that any impact will be significant.

9.1.5.2 Snagging hazards

A number of subsea structures and residual footprints have the potential to present a snagging risk to fishing vessels. For example, anchor mounds created by the drilling rig, the manifold, wellheads and flowlines. Structures are designed to be fishing friendly i.e., they have raked sides that deflect trawl boards and will be within an enforced 500m safety zone.

9.1.5.3 Accidental Events: spills of hydrocarbons (>10 tonnes)

In the very unlikely event of a major crude oil spill, there is potential for damage to fishing vessels passing through the project location at the time of the event and potential for a decrease in catch if fish stocks are affected. It is expected that if boats are present in the area at the time of a spill they will be able to avoid the slick so it is considered highly unlikely that gear or boats will be damaged. However, vessels may be excluded from the affected area during

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the clean-up operations. Generally, for short periods of time the fishing industry can relocate to other grounds without any detrimental impacts to catch, but a spill that affects large areas of sea may make it harder to relocate. It fish stocks are contaminated they make take a number of years to recover and fishing grounds could be closed with substantial loss of income for industry. Experience from major spills has shown that the long-term effects on wild fish stocks are unlikely because the normal over-production of eggs provides a reservoir to compensate for any localised losses. However, there could be a loss of market confidence as people may be unwilling to buy fish caught in a contaminated area.

9.2 SHIPPING AND NAVIGATION

9.2.1 Baseline Data Sources

This section makes use of the following data sources:

Technical report on existing activities within SEA 2 (DTI 2001e)

Charting Progress 2: The State of UK Seas - a report by the UK Marine Monitoring and Assessment Strategy community (UKMMAS 2010)

Consent to Locate - Alma (Technical Note) (Anatec 2011) 9.2.2 Existing Baseline

Shipping activity is economically important for the east coast regions of England and Scotland and provides links with northern Europe from the Port of Tees and Hartlepool and from ports in the Firth of Forth, e.g., Rosyth and Edinburgh (UKMMAS 2010). The CNS experiences moderate levels of shipping traffic associated with a number of major ports located along the coast. These include international ports, import/export facilities, roll on – roll off (ro-ro) facilities, ship building yards, container and ferry services, bases for the offshore oil and gas industry and commercial fishing facilities. The majority of routes transiting the Alma field have an average of 0.5 to 1 daily vessels passages, with some routes experiencing daily passage of 1-10 vessels (DTI 2001e). At the time of preparation of the Anatec Consent to Locate document (Anatec 2011), the Galia development was considered to be an Alma production well and not shown separately (it can be assumed that for the Consent to Locate document, Galia forms part of the Northern Drill Centre). The Galia production well location has added to Figure 9-3 and it can be seen that of the closest routes; 4, 6, 7 and 8 pass closer to the new well location than to the Northern Drill Centre, however routes 1 and 2 are further away from Galia. Tables 9-3 and Figure 9-3 below show that there are fourteen ship routes that pass within 12 nautical miles (nm) of the Alma and Galia development.

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Table 9-3: Ship routes Route Description FPSO Northern Drill Southern Drill Ships % of No. Centre (including Centre Per Total Galia) Year CPA Bearing CPA Bearing CPA Bearing (nm) (°) (nm) (°) (nm) (°) 1 Humber-Boknafjorden b* 1.2 299 0.5 119 0.6 299 50 5% 2 Aberdeen-Esbjerg* 3.2 16 2.8 16 4.6 16 70 7% 3 Norway S-Tees* 3.4 147 4.9 147 3.2 147 70 7% 4 Aberdeen-Fife* 5.2 204 5.3 204 3.7 204 26 3% 5 Volve Field-Rotterdam* 5.6 78 7.0 78 7.1 78 62 7% 6 Lerwick-Amsterdam Direct 5.6 242 4.6 242 3.9 242 8 1% 7 Norway S-Seaham* 5.9 326 4.4 326 6.1 326 10 1% 8 Humber-Boknafjorden a* 6.6 296 4.8 296 5.9 296 200 21% 9 Canada-Hamburg* 7.1 214 6.9 214 5.5 214 100 11% 10 Hamburg-Moray Firth* 7.1 214 6.8 214 5.4 214 25 3% 11 Tyne-Norway S* 7.2 330 5.8 330 7.6 330 20 2% 12 Tyne-Kattegat* 8.2 157 9.5 157 7.7 157 235 25% 13 Hamburg-Kirkwall 9.9 41 10.4 41 11.6 41 15 2% 14 Montrose-Esbjerg* 11.5 194 11.8 194 10.0 194 45 5% Total 936 100% * Where two or more routes have identical Closest Point of Approach (CPA) and bearing they have been grouped together. In this case, the description lists the sub-route with the most ships per year Source: Anatec (2011)

Figure 9-3: Shipping Route Positions within 10nm of Alma and Galia Locations

Source: adapted from Anatec 2011

The fourteen shipping routes are trafficked by an estimated 936 ships per year passing within 12nm of the Alma and Galia locations. This corresponds to an average of 2 to 3 vessels per day. The majority of these vessels are either cargo ships or tankers, with the highest percentage of these vessels being 1,500 - 5,000 tonnes in size. The only route to pass within 2nm of Alma and Galia (Route 1) is used by an estimated 50 vessels per year between Humber and Boknafjorden in Norway. The route passes northwest of the FPSO location at a mean distance of 1.2nm, southeast of the northern drill centre at a mean

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distance of 0.5nm and northwest of the southern drill centre at a mean distance of 0.6nm. The next closest mean route position passes over 2nm from the Alma and Galia locations (Anatec 2011). In addition, a moderate number of fishing vessels will be present in the area surrounding the Alma development (Maritime Data 2011). Collision Risk Accident frequency statistics (OGUK 2009) give an overall annual collision frequency of 8.5 x 10-3 per installation for all offshore oil and gas operations between 1990 and 2007 (33 incidents). 15 incidents during this period involved collisions with mobile drilling units (frequency 0.014 collisions per installation over the period 1990 to 2007, but only one collision occurred between 2000 and 2007, giving a frequency of 2.2 x 10-3 collisions per installation over this period). No collisions involving FPSOs occurred during the reporting period. There is no collision risk associated with the operational phase of the Galia development, however as calculated in the Alma ES, the annual ship collision frequency for the EnQuest Producer FPSO at Alma is estimated to be 1.8 x 10-4 (Anatec 2011). Lack of an incident involving FPSO prohibits comparison of the above modelled result with historic data. Comparison with the historic data for mobile drilling units needs also to consider the risk profile, in that the supply activity associated with a mobile drilling unit is likely to be considerably higher.

9.2.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect shipping and navigation are tabled below. As all of the identified activities have been determined (by the EIA) to have potential for residual impact, they are all shown in bold. Table 9-4: Shipping and navigation – potential impact identification Project Activity Aspect Potential Impact Construction Exclusion zone could Physical presence and movement Physical presence and impede shipping routes of vessels movement of vessels Increased collision risk Production Exclusion zone could Increased movement of export Increased vessel activity impede shipping routes tanker and supply vessels in region Potential collision risk Accidental Events Chemical / hydrocarbon release Diesel, crude or Damage to vessels (>10 tonnes) chemical spill (including Restrictions on shipping OBMs) routes 9.2.4 Control & Mitigation Measures

Mitigation measures will be as per Section 9.1.4 with the addition of the following:

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A 500m safety exclusion zone around the drilling rig will be enforced.

All construction and operation vessel movements will be kept to a minimum.

The drilling rig and support vessels will be appropriately lit and sound warnings will be broadcast in poor visibility.

Other users of the sea will be notified of the presence and intended movements of vessels associated with the development through Kingfisher fortnightly bulletins, notices to mariners, and regular VHF radio broadcasts.

All vessels associated with the development will follow IMO Standards and will be properly marked.

An OPEP will be in place to help manage response to any spills and pipelines will be tested to ensure integrity.

EnQuest will have a collision risk management plan in place for the proposed development, compliant with IMO standard requirements. 9.2.5 Residual Impact Significance Assessment

9.2.5.1 Physical presence and movement of vessels

The nearest shipping route is within 2nm of the Galia development. During construction, some shipping will be displaced from the immediate vicinity of the development; however there is ample sea room to do so. The 500m safety exclusion zone around the drilling rig is intended to prevent potential collisions with any vessels that may be in the area. This will be enforced by a guard vessel. As such, it is concluded that the presence and movement of vessels will have no residual impact on shipping and navigation.

9.2.5.2 Accidental events: spill of hydrocarbons (>10 tonnes)

Spill modelling (Section 6.3 and Appendix B) shows that in the event of a total loss of containment from the FPSO and/or export tanker (due to collision with each other) or a total loss of well control; depending on the prevailing wind conditions at the time, large areas of the North Sea area could potentially be affected if no intervention measures are taken. However, an incident of this magnitude is unlikely. If the spill is extensive then shipping routes in the region could be affected by oil spill response operations. There is the risk of economic impacts on shipping associated with longer routes and delays. Due to the rarity of such an event, the residual impact has been assessed as being insignificant.

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9.3 OTHER MARINE USERS

9.3.1 Baseline Data Sources

Sources of data used in this section include:

Data from the Crown Estate on offshore windfarm areas and marine aggregate dredging sites (Crown Estate 2011)

Oil and gas infrastructure data (UKDeal 2010)

Atlas of recreational boating (RYA 2008)

Cables data (KISCA 2010)

Admiralty charts for the area showing military practice and exercise areas 9.3.2 Existing Baseline

Other marine users are all users of the marine environment, other than commercial fisheries and shipping which have been assessed separately in this report. This includes (but is not limited to) recreational users, other oil and gas developments and wind farm installations. The closest activities to Galia are other offshore oil and gas exploration and production (See Figure 9-4), and the following oil and gas infrastructure are located within 40km;

123 wells (see Table 9-5); one platform (Clyde), one FPSO (Janice Alpha) and 4 pipelines.

Clyde platform, located 38km northwest of the drill centre.

One pipeline transects Block 30/24. This is the Norpipe system Ekofisk 2/4J to Teeside oil pipeline which runs through the north east corner of the Block, 13.5km north-west of the drill centre. Table 9-5: Wells within 40km of the development Activity Status Completed Suspended Plugged and Unknown Total abandoned Appraisal 7 6 8 1 22 Exploration 4 2 45 1 52 Development 18 16 15 0 49 Total 29 24 68 2 123

Other marine users in the vicinity of the project include:

Seven telecommunications cables within 40km of the project area. The closest cable is the Norsea AS cable which links the Valhall complex and the Clyde platform. At its closest point the cable is 32km north east of the drill centre.

The Dogger Bank Round 3 licensed wind farm zone is located 53km to the south of the Galia drill centre.

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3 Recreational boating - a lightly used recreational sailing route passes through the centre of Blocks 30/24 and 30/25, 5km north-west of the drill centre. There are several yachting routes, general sailing areas and racing areas near the coast but the development is far enough offshore for general sailing not to occur in the vicinity (RYA 2008).

Marine aggregate dredging site, Area 466/1 application area, licensed to Cemex UK Marine Ltd, is the closest to the project area, situated 138km south-west of the Galia drill centre.

There are no military practice and exercise areas (PEXA) or munitions dumping sites within 100km of the project area. 9.3.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect other marine users are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact. Table 9-6: Other marine users’ potential impact identification Project Activity Aspect Potential Impact Construction Localised displacement of Physical presence and other marine users movement of vessels Physical presence and movement Increased collision risk of vessels Anchoring Increased collision risk Production Increased movement of export Increased vessel activity Increased collision risk tanker and supply vessels in region Accidental Events Chemical / hydrocarbon release (< 1 tonne) Diesel, crude or Chemical / hydrocarbon release chemical spill (including Damage to vessels (1-10 tonnes) OBMs) Restricted access Chemical / hydrocarbon release (>10 tonnes)

The likelihood of activities affecting other marine users was assessed as being unlikely given the historical use of the development area for oil and gas activity. If impacts were to occur they would be relatively site specific, low in magnitude with a short-term duration.

9.3.4 Control & Mitigation Measures

Marine users will be notified of the presence and intended movements of construction vessels and the presence of new structures via the Kingfisher

3 Light Recreational Route - as defined in the UK Coastal Atlas of Recreational Boating, RYA 2008

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fortnightly bulletins, Notices to Marine and, where appropriate, VHF radio broadcasts. In addition, EnQuest will have a collision risk management plan in place for the proposed development, including the deployment of a guard vessel on station.

9.3.5 Residual Impact Significance Assessment

9.3.5.1 Accidental events: spill of hydrocarbons (>10 tonnes)

Spill modelling (Section 6.3 and Appendix B) shows that in the event of a total loss of containment from the FPSO and/or export tanker (due to collision with each other) or total loss of well control; depending on the prevailing wind conditions at the time, large areas of the North Sea area could potentially be affected if no intervention measures are taken. Oil spill modelling indicates that oil has the potential to beach along the coast. In this situation there is the potential that near shore recreation could be affected if restrictions are imposed to assist with response operations. There may also be knock-on effects on the tourist industry if the spill beaches in substantial quantities. However, due to the rarity of such an event, the residual impact has been assessed as being insignificant.

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Legend Galia Field Development Environmental Statement Median Line Figure 9-4: Other Marine Users Land Block Date Friday, March 2, 2012 13:31:50 Projection ED_1950_UTM_Zone_31N ^_ Galia Well Spheroid International_1924 XW EnQuest Producer FPSO Datum D_European_1950 .! Alma Production Centre Data Source The Crown Estate, ESRI, UKDeal, KISCA .! Alma Water Injection Centre J:\P1459\Mxd\Environmental Statement\Galia ES\ File Reference Figure 9-4 Other Marine Users.mxd XW FPSO )" Platform Produced By Emma White A Well Checked Pipeline Reviewed By Louise Mann Cable route Hydrocarbon Field

Round 3 windfarm

UK aggregate application area NOTE: Not to be used for navigation km © Metoc Ltd, 2011. 04.5 9 18 27 36 45 All rights reserved. ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

9.4 ARCHAEOLOGY

9.4.1 Baseline Data Sources

Prehistoric Archaeology Data concerning the general submarine archaeology of the North Sea was compiled as part of the Strategic Environmental Assessment for areas SEA2 and SEA3 (Flemming 2002). In addition, some information is available under the aegis of the Aggregates Levy Sustainability Fund (ALSF). This represents a pilot study and is currently restricted to near coastal areas (Wessex Archaeology 2008). Historic Remains Information on the status of wrecks is available through the Maritime and Coastguard Agency (MCA 2011).

9.4.2 Existing Baseline

9.4.2.1 Prehistoric archaeology

As a result of a series of glaciation episodes peaking at about 280,000 yrs before present (B.P.), 150,000 yrs B.P. and 20,000 yrs B.P., the sea bed of what is now the North Sea has been repeatedly exposed. There is significant evidence that areas of the North Sea not covered by ice were habitable. Older remains (>100,000 yrs) are unlikely to have been preserved as far north as Galia, because the area was glaciated prior to this. However more recent artefacts may be present. At its greatest extent, some 15,000yrs B.P. the so- called Doggerland may have extended as far north as 61°N, with the Alma area remaining as dry land for about 5000 years. It is possible, therefore, that individual artefacts, such as stone tools, or remains of settlement sites could be encountered during operations at Galia. If properly reported and conserved such remains could provide significant information concerning early human development in the Doggerland region. It is likely that any sites discovered will be within the jurisdiction of the Ancient Monuments and Archaeological Areas Act 1979. While this act is primarily land based, it has also been applied to provide some protection for underwater sites. The Act provides for the scheduling of ‘monuments’, which encompasses buildings, structures or work, cave or excavation, vehicle, vessel, aircraft or other movable structure. In order to be eligible for scheduling, a ‘monument’ must be of national importance. Geophysical and geotechnical survey results (Gardline 2011) do not show any anomalies typically associated with archaeological sites.

9.4.2.2 Historic remains

Throughout the historical period there have been important trade and other routes across the North Sea. While the majority of wrecks resulting from natural events (storms etc) are likely to be coastal in nature, some may have occurred in deeper water. The more likely cause of deep water wrecks (including aircraft remains) is wartime activity.

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Wreck material (broadly any artefact on the seabed as a result of once being on board of or part of a vessel) is presumed to have an owner irrespective of date of loss. It is a legal requirement (under section 236 of the Merchant Shipping Act 1995) that recovered wreck material should be reported to the Receiver of Wrecks. Three key pieces of legislation (MCA 2011) applicable to the protection of wrecks in UK waters are: Protection of Wrecks Act 1973 This act provides for

Protection for designated wrecks which are deemed to be important by virtue of their historical, archaeological or artistic value.

Protection for wrecks that are designated as dangerous by virtue of their contents (e.g. ammunition transporters). The Protection of Military Remains Act 1986

This Act makes it an offence to interfere with the wreckage of any crashed, sunken or stranded military aircraft or designated vessel without a licence. This is irrespective of loss of life or whether the loss occurred during peacetime or wartime. All aircraft which have crashed while on military service (including non-UK) receive automatic protection, but vessels must be individually designated.

Sites may be designated as Protected Places (automatic for military aircraft, but for vessels requires designation by name, although the location may not be known) or as Controlled Sites. Ancient Monuments and Archaeological Areas Act 1979

As previously noted, it is possible that any wrecks discovered will be within the jurisdiction of the Ancient Monuments and Archaeological Areas Act 1979. There are no known wreck sites (or any other historical remains) within the Galia area and no indication from the survey data (GEL 2011) that any such sites are likely to be present. If present, remains may be fragmentary, particularly where these are a result of wartime activity. Part of the reason for protection of such sites is the risk of munitions being present in the vicinity of the wreckage. Unexploded munitions are not rendered safe on immersion in water, and may become dangerously unstable.

9.4.3 Potential Impact Identification

The EIA (tabulated in Appendix A) identified project activities with the potential to interact with the environment. Those with potential to affect archaeology are tabled below. Those shown in bold are those which the EIA determined have potential for residual impact.

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Table 9-7: Archaeology potential impact identification Project Activity Aspect Potential Impact Construction Physical presence and movement Anchoring of vessels Physical damage to Physical presence of existing and undiscovered subsea infrastructure Installation of flowlines archaeology and flowlines Trenching Accidental Events Physical damage to Overboard loss of equipment or Dropped objects existing and undiscovered waste archaeology

The impact of disturbance of an archaeological site is related to the cultural value of a site. This is likely to be increased if a site:

Establishes evidence of human occupation in areas where there was no previous evidence

Contains examples of previously unknown or poorly preserved artefacts

Is of historical significance Uniquely among environmental impacts the discovery of archaeological remains provides an opportunity for positive (i.e., beneficial) impact if such remains are promptly reported and made available for preservation. It is not possible to predict the finding of submerged pre-historic sites. However, if found such discoveries will be of inestimable importance to our understanding of the early settlement of North West Europe. Correct recording and preservation of any artefacts or remains found is both a legal obligation and would be likely to have a positive reputation value.

9.4.4 Control & Mitigation Measures

The British Marine Aggregate Producers Association (BMAPA) has produced a protocol for reporting finds of archaeological interest (Wessex Archaeology 2005). This has the specific aim of reducing adverse effects of marine aggregate dredging on the historic environment. However, it is equally applicable to other industries working in the North Sea. These protocols will be followed in the event of discovery of artefacts on the seabed, which could potentially be of archaeological significance.

9.4.5 Residual Impact Significance Assessment

In the unlikely event of a site discovery, the proposed mitigation measures would ensure damage to the site would be minimised and the nature of the discovery properly reported. It is therefore likely that any damage would be of minor significance, while the value of the discovery may be of moderate/major (positive) significance.

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10 CUMULATIVE AND INDIRECT IMPACTS

As discussed in Section 4.2, the EIA has given consideration to cumulative and indirect impacts and interactions. It is difficult to quantify the project indirect impacts but where possible this was undertaken as part of the main EIA. For example, the potential for chemicals to bioaccumulate up the food chain and affect the top predators such as seabirds and marine mammals. In addition, the EIA also considered cumulative impacts from similar activities within the project e.g., the combined effects on habitat loss from numerous types of seabed disturbance. The results of this assessment are already discussed in Sections 8 and 9 and in Appendix A. This Section focuses on the potential for cumulative and indirect impacts and interactions relative to Galia and:

Past and future oil and gas developments (Section 10.1)

Other seabed/marine users e.g., commercial fishing, wind farms, marine aggregate extraction (Section 10.2)

Climate change (Section 10.3)

10.1 OTHER OIL AND GAS DEVELOPMENTS

The Galia development lies in a mature oil and gas producing area within the CNS. There is little current existing infrastructure in the immediate are of the development, with the nearest oil and gas activity at the Clyde platform 38km to the north west. However, the long established and on-going oil and gas exploration and production activity of the wider region gives rise to the potential for cumulative environmental impacts. Galia will be developed alongside the Alma field development and will be tied back to the Alma production centre. It should be noted that Hess are planning to carry out the decommissioning of their Fife, Fergus, Flora and Angus fields. The timing of this decommissioning will depend on gaining approval from the DECC (draft programme is currently under consideration). If approval is granted in early 2012 then offshore operations would continue until late 2015. The Galia development is approximately 22km north-west from the closest of these fields (Angus). Given the distance of Galia it is unlikely that any cumulative impacts will arise.

10.1.1 Deterioration in Local Air Quality

The EIA concluded that the meteorological conditions in the CNS were of sufficient strength to enable rapid dispersion and dilution of SOx and NOx emissions from construction and production activities. Air dispersion modelling indicated that gas concentrations would be significantly below guideline levels for human health and environmental protection within 500m of the discharge point i.e., from either a vessel, rig or the FPSO (see Section 7.1.5). The majority of the Galia construction emissions will occur in the vicinity of the FPSO, 38km from the nearest existing installation and 280km from the nearest coastline. In conclusion, Galia is considered to be sufficiently distant from any

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planned or existing developments such that a cumulative impact of emissions on air quality is unlikely to occur. The effects of the gases on the Galia workforce are dealt with under occupational health regulations and are out of scope of this assessment.

10.1.2 Deterioration in Water Quality

During construction at Galia, there is likely to be chemical discharges including discharges of WBM. There may also be occasional discharge of chemicals during production if the FPSO water injection system is offline. The chemicals discharged are relatively benign, the majority being risk assessed by the CEFAS as HQ colour band Gold or OCNS category E. These are categories for products that present the lowest hazard to the environment. Residual currents are such that chemical discharges are likely to be rapidly diluted and dispersed (see Section 7.3). The discharge of chemicals will be short term and the Galia well will be drilled sequentially with the Alma wells, reducing any combined toxic impacts. All of the five installations within 50km of the Galia project area (Clyde, Auk A, Fulmar AD, Ekofisk and Judy) discharge produced water to the marine environment (DECC 2011c). Historic research has shown that, due to the rapid dilution, low concentrations and low toxicities of contaminants in produced water, discharges in the North Sea have low potential for biological impact (Wills 2000). Dilutions required for no observed effect concentration (NOEC) are achieved within five minutes, within 10m to 100m from the discharge point. As the nearest of the five platforms to Galia is 38km (i.e., Clyde), it is likely that there will be little or no residual hydrocarbon contamination, during normal operational activities, from other developments around the project area, therefore cumulative impacts are not expected. Given the mitigation measures in place and the distance to the nearest discharging facility (Clyde), cumulative effects on water quality are unlikely. Therefore, no significant cumulative impacts on water quality are expected during the construction or production phases of the Galia development with the other installations in the vicinity of the development (including Alma).

10.1.3 Disturbance of Seabed Sediments

As discussed previously, the combined potential seabed disturbance from all sources at Galia is a maximum of 0.33km2 (see Section 5.5.3). The EIA has concluded that the development will have a minor impact on seabed sediments. Disturbance may be visible for up to 5-10 years after construction in the form of anchor/chain footprints, or the presence of cuttings piles. However, in general, although disturbed, the composition of surface sediments in the development area will remain unchanged. In addition, given background levels of contamination associated with the previous use of the area for oil and gas development, levels of hydrocarbon contamination are not expected to increase above existing historical levels. No lasting effect on seabed conditions is expected.

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It can be assumed that a similar level of disturbance will be observed at the other field developments planned for the CNS. Generally, the development projects are widely spread and footprints will not overlap. It is possible cumulative impacts relative to discharges from neighbouring oil and gas facilities operating contemporaneously may arise. However, the closest discharging facility (Clyde) is 38km from Alma and Galia, suggesting a low potential for cumulative impacts. There were areas of disturbance noted in the site survey of Galia that corresponded with the previous development of the field. However given the length of time since the last disturbance at the field occurred these are unlikely to be of any significance. Therefore no cumulative impacts are likely to occur with the new Galia development.

10.1.4 Disturbance of Habitats or Species

Drill cuttings The only other oil and gas development within 40km of Galia which is known to be under construction at the same time is the Alma development. These will be over 5km distant which is well beyond the range at which there can be noticeable impacts. Therefore no cumulative impacts on habitats or benthic species are anticipated as a result of this aspect of the development in combination with any other development. Disturbance The seabed in immediate vicinity of the Galia development is likely to be visibly disturbed on completion of trenching, backfilling and deployment of anchors from the pipeline installation vessel. On retrieval, the anchors are expected to leave a small area of disturbance, much of it which will comprise mobile/loose sediments rather than clay. The Galia field will be developed alongside the Alma field. The flowlines at the Alma development will now all be trenched in the same manner as at Galia. Four trenches will be cut from the Alma production manifold back to the FPSO and two trenches will be cut from the FPSO to the WI centre. All trenches will have a maximum footprint (width) of 20m per trench. Therefore the production trenches will have a maximum footprint of 0.24km2 and the WI trenches 0.1km2. Consequently the total maximum footprint from trenching at Alma will now be 0.34km2. The fields are so close together as to be considered one development, with a maximum combined footprint of 0.66km2. As there are no other oil and gas developments within 40km, it is unlikely that there will be any cumulative impacts from this aspect of the development. Subsea noise The main subsea noise source at Alma is piling. There will be no piling at Galia and therefore no cumulative impacts from this aspect of the development.

10.1.5 Transboundary Impacts

The proximity of the development to the UK-Norway median line (closest point 22km) also means that transboundary effects must be considered. This will include interaction between the human environments either side of the boundary and the potential for impacts to protected sites or species within UK waters to transfer into protected sites in Norwegian waters. The scale and

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consequence of any trans-boundary effects will be comparable, or less, to those in UK waters. In the event of an oil spill entering Norwegian waters it may be necessary to implement the NORBRIT Agreement (the Norway-UK Joint Contingency Plan), which sets out command and control procedures for pollution incidents likely to affect both parties.

10.2 OTHER SEABED USERS

In general, there are two main cumulative impacts to be considered when assessing the effects of a project on the surrounding region. These are:

Whether the combined footprints of overlapping projects have the potential to exacerbate the environmental impacts from the respective projects.

Whether projects that do not overlap, when considered in combination, will result in the loss or disturbance of substantial areas of a particular regional habitat. 10.2.1 Commercial Fishing

There are potentially two types of cumulative impacts associated with fisheries: physical disturbance of the seabed and effects on marine ecology. The ES has demonstrated that, given the highly dynamic environment within the project area, physical disturbance, as a result of construction activities, is unlikely to be noticeable above background levels within a minimum of 5 years of the these activities ceasing (Sections 7.4, 8.3 and 9.1). In addition, the community type in the project area is typical for the region and it is considered that the combination of disturbance from trawling and construction will not cause an overall significant loss of habitat type or change in community structure.

10.2.2 Offshore Wind Farms

Offshore wind farms are becoming more prevalent in UK waters, of which the “Zone 3 - Dogger Bank” (Round 3) is the closest, located 53km to the south of the proposed Galia field development. The zone has been awarded to the developer Forewind4 (Crown Estate 2011). The first phase is expected to be ready for construction in late 2014. The site is anticipated to have an overall production capacity of 13GW of energy. Due to the distance of the wind farm from the Galia development, it is unlikely that there will be any in combination effects from habitat removal, sediment disturbance and noise generation from piling during construction, especially as the wind farm will not start construction until after completion of construction at the Galia development.

10.2.3 Marine Aggregate Extraction Areas

The closest marine aggregate dredging site is the Area 466/1 application area, licensed to Cemex UK Marine Ltd, situated 138km south-west of the Galia drill centre. Impacts on the marine environment from aggregate extraction primarily relate to the direct disturbance of the seabed and the corresponding effects on

4 Forewind Consortium – comprising four partners ; SSE (Scottish and Southern Energy plc); RWE npower renewables, the UK subsidiary of RWE Innogy, and two of Norway’s largest companies, Statkraft and Statoil (Crown Estate 2011)

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marine ecology. Impacts are generally restricted to the area of seabed licensed; although, depending on the dredging activity and prevalent hydrodynamic conditions, sediment plumes from aggregate screening may impact benthic communities within a radius of a few kilometres from the license zone. Due to the distance from aggregate extraction sites, in-combination effects with the Galia development are unlikely.

10.3 CONCLUSION

The EIA identified the Galia development will not have any residual impacts on water depth, wind speed or wave conditions. Residual impacts on the environment will be short-term, predominantly affecting marine ecology. As climate change has the potential to affect the biological baseline it is possible that the project can act in combination with climate change to exacerbate this impact. However, the EIA concludes that, following construction, biological communities are anticipated to recover to pre-impact levels/structures or similar within five years (see Section 8.2). Given the relatively short timescale of the construction impacts, it is considered unlikely that any cumulative impacts from the project and climate change will have significant impacts on marine ecology.

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11 ENVIRONMENTAL MANAGEMENT

This section provides an overview of the management systems in place at EnQuest. EnQuest arrangements for environmental management are part of an integrated management system, and this section therefore describes the management tools EnQuest have in place which cover health, safety, environment and quality (HSEQ). The section also describes how the control and mitigation measures proposed in this ES will be adopted and bridged into the wider context of the EnQuest Health, Safety and Environmental Management and Quality systems.

11.1 MANAGEMENT SYSTEM

EnQuest is a socially responsible employer, committed to maintaining high standards in health, safety and environmental performance. EnQuest implements and operates an integrated Health, Safety and Environmental Management System (HS&EMS) which has been accepted and endorsed by the Board, and embedded in the overall business culture. The HS&EMS is an integral part of the overall management system. It is laid down in policies, procedures, standards and work instructions. Its general purpose is to prevent EnQuest’s activities from putting people, the environment, property or the reputation of the company at risk. The OSPAR verified HS&EMS is designed to match the requirements of ISO- 14001:2004 and is based on the requirements of the Health and Safety OHSAS 18001 standard. The purpose of the HS&EMS is to enhance health, safety, environmental and quality (HSEQ) performance and provide a framework for HSEQ management for all of the activities carried out throughout the company. The management systems are designed to cover HSEQ aspects which EnQuest can control and directly manage and those it does not control or directly manage, but can be expected to influence.

11.2 PROJECT SPECIFIC ENVIRONMENTAL MANAGEMENT

A project specific HS&E plan has been developed to cover both the Alma and Galia developments which will define how EnQuest will manage HS&E risks and activities (EnQuest 2011b). The Project HSEQ Engineer is responsible for maintaining and implementing the plan, and for providing HSEQ controls within the project to ensure that the requirements of the EnQuest HSEQ management systems are met. The Project HSEQ Engineer reports directly to the Development Manager, who is accountable for the project as a whole and will implement and maintain a number of documents and processes which include:

Project HSE and Quality Plans

Regulatory Compliance Procedure

Risk management system

Document management control

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However, everyone working on the project either directly or indirectly has a responsibility for ensuring that they meet defined HS&E requirements for their own particular activities. The combined Alma and Galia development HS&E plan (EnQuest 2011b) describes how EnQuest will manage HS&E activities arising from the developments. This Plan applies from the concept selection stage through to the project execution phases of the project and:

Describes how EnQuest will manage the HS&E aspects arising from the project

Presents the key HS&E requirements of the project

Clearly defines HS&E roles and responsibilities

Provides a vehicle for tracking and monitoring

Provides an auditable trail for Project HS&E management

Sets out EnQuest’s environmental targets as shown in Table 11-1 Table 11-1: EnQuest environmental targets Objective Target Comment All permits in place and permit Compliance with consent conditions identified to contractors. Exception requirements Reporting No deviations from permit requirements No breaches of waste regulations Compliant management of Exception waste Waste categorisation and monitoring Reporting sufficient for EEMS reporting Assurance that the Rig and Confirmation of appropriate and Verify through Installation Vessels are fit effective rig/vessel audit regime. Audit Report for purpose No incidents or spills Well testing is efficient with Assurance that UK Oil Guidelines Exception respect to atmospheric followed reporting emissions Improvement opportunities Specific improvement opportunities Lessons learned for future project activities identified and recorded at close out. Register identified Implement an action Ensure all actions are tracked and Company has tracking system to track lessons learned are circulated implemented the environmental audit Synergi Action actions and lessons Tracking System learned and has trained specific personnel in it’s use Ensure all contractors meet To conduct an Environmental Systems To be applied to or exceed Enquest and practices audit prior to contract all key contractors Environmental award and conduct continuous and sub- expectations and standards monitoring after award. contractors Improve Licences, Permits Implement a tracking system to ensure Enquest have and Consents applications timely submission and approval of researched the

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and tracking process regulatory applications. To be in place market to end Q1 2012 evaluate available systems. Improve individual Conduct a series of town hall meetings Supported by responsibility and and initiatives to cascade posters and awareness for the Environmental targets and expectations initiatives. environment to all personnel Additional personnel resources identified and in place now in place Source: Extracted from EnQuest HSEQ policy 2011 All contractors will be requested to develop their own HS&E Plans, which are aligned to the EnQuest Project HSE Plan and are in line with EnQuest project goals and objectives. Compliance with relevant HS&E regulations, codes and standards also needs to be common across all of the companies that will participate in the development. Competency of contractor personnel and contractor’s means of achieving a competent workforce for EnQuest projects will be identified in the HSE Plan, assessed in contractor selection and monitored during contractor duration. During construction bridging documents will be in place between the contractors and EnQuest. These will describe the management structure and division of responsibilities, the methodology of execution of the work programme and any emergency response procedures. EnQuest actively monitor and audit contractor’s operational control procedures and their implementation. For example, contractor’s proposed method statements, programmes and resources are reviewed during contractor selection (procurement) and all plans, procedures and standards for operational control are reviewed and approved by EnQuest. The project will be subject to statutory regulatory control which requires various applications and notifications to be made to nominated governmental bodies for approval of the relevant activities. Effective management of these activities is critical for the success of the project and to enable this EnQuest will establish a Permits Licenses Approvals Notifications and Consents (PLANC) register. The register will be regularly monitored to ensure that the necessary consents or notifications are in place when required during the development. The HSEQ Engineer will develop and manage the PLANC register. The following are the key permits and consents requirements:

Environmental Statement (ES) approval

Field Development Plan (FDP) approval

Pipelines Works Authorisation (PWA)

Petroleum Operations Notices (PON) approval e.g., PON15C (pipelines), PON15B (drilling), PON15D (production)

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Oil Pollution Emergency Plan (OPEP)

Operational permits e.g., Vent consent, flaring consent, European Union Emissions Trading Scheme (EU ETS) (Greenhouse Gases (GHG) and New Entrant Reserve (NER))

11.3 MANAGEMENT OF CONTROL & MITIGATION MEASURES

Mitigation measures identified in the EIA process and reported in this ES will be adopted and bridged by EnQuest’s HSEQ Management System through the PLANC register. In addition to the standard best practice mitigation measures, including those that are regulatory requirements, which will be enforced during construction and production (see summary in Table 11-2 and Appendix A), a summary of EnQuest’s commitments relating to the Galia development is given in Table 11- 3. Table 11-2: Summary of control & mitigation measures Mitigation measures Ensure all machinery is maintained and serviced Use of cleaner low emission fuels. Stack heights in accordance with the relevant regulations. Ensure all machinery used for transfers is regularly cleaned and maintained. Every vessel will have and implement a written waste management plan, compliant with MARPOL 73/78. Annex V (Garbage) is particularly relevant. No plastics/plastic containing material will be disposed of at sea, regardless of location. Paper & food wastes will only be discharged outside the 12nm limit. General household products will be selected that are environmentally benign. Daily recording of chemical use to allow more refined and efficient use. Where possible chemicals will be recycled (returned to rig for use in other sections), skipped and shipped or re-injected and not discharged. Selections of chemicals will be made in accordance with the CEFAS ranked list, where chemicals ranked as lower potential hazards are preferentially chosen. Only chemicals permitted through the relevant Offshore Chemicals Regulations chemical permit (i.e. PON15B, C or D) and that have been subject to a risk assessment will be discharged. All oil discharges will be covered by an approved OPPC permit. The footprint of any anchors, infrastructure and protective structures will be minimised A 500m safety exclusion zone will be in place around the FPSO and drilling rig at all times, enforced by designated guard vessel The FPSO, drilling rig and support vessels will be appropriately lit. The tanker and supply vessels will follow defined routes. All relevant notices will be placed in the Kingfisher Bulletin and “Notice to Mariners” All subsea structures have been designed to be fishing friendly Any produced water discharge will be closely monitored to ensure that all contaminants are

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Mitigation measures at an acceptable level. Oil in water, chemical, aromatic and radionuclide concentrations will all be reported via the appropriate OCR permit i.e., PON15D. Any produced water potentially contaminated with reservoir hydrocarbons will be recycled or re-injected and not discharged unless below permitted levels for discharge via an Oil Pollution, Prevention and Control (OPPC) permit. A location specific approved OPEP will be in place for the development that covers drilling and production. The OPEPs will detail all emergency procedures that will be in place to minimise any spill. Control measures will be in place to ensure rapid response to loss of pipeline containment. These will be outlined in the OPEP. Accidental spills will be kept to a minimum through training, good housekeeping and through storage/handling procedures e.g., sumps, drains and bundling should catch accidental spills. Management controls will be in place to eliminate bunkering spills e.g. only bunkering during day light and in good weather. EnQuest has access to Tier 1, 2 and 3 oil spill response capabilities through Oil Spill Response Limited (OSRL). EnQuest is a member of OSPRAG which will provide support in a well blow out event. Every reasonable measure will be taken to retrieve dropped objects. If the object cannot be retrieved a PON2 will be submitted to the DECC. A dropped objects plan will be developed to address risk of dropping objects during construction and operations.

Table 11-3: Summary of commitments Aspect Commitment Archaeological EnQuest will follow the reporting protocol published by the BMAPA remains Atmospheric Emissions will be minimised through maintenance of power generating equipment and emissions use of lower emission fuels. Minimisation of chemical usage is a priority and EnQuest will actively seek products that are deemed to have minimal environmental impacts (i.e., low toxicity, low Chemical Use and bioaccumulation potential and high biodegradability). Discharge Where required chemicals will be included in a PON15 chemical permit application

EnQuest will risk assess and seek to minimise chemical discharges in order to reduce or eliminate toxic impacts of the development on water or sediment quality. Collision All vessels associated with the development will be properly marked and lit with appropriate sound signalling in poor visibility conditions An IMO compliant collision risk management plan will be in place Other users of the sea will be notified of the presence and intended movements of vessels associated with the development through Kingfisher fortnightly bulletins, notices to mariners, and regular VHF radio broadcasts. Permanent 500m exclusion zones will be maintained at the Galia well Vessel movements will be kept to a minimum A debris clearance survey will be carried out prior to each rig move Subsea equipment associated with the Galia development will be subject to dropped Dropped Objects object studies. Dropped objects that cannot be retrieved, will be reported to the DECC on a PON2 form so that other sea users can be notified of their presence. Environmental EnQuest will include environmental controls at all project inductions and vessel Controls mobilisations

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Footprint The footprint of the development will be kept to a minimum The JNCC ‘Statutory nature conservation agency protocol for minimising the risk of Noise injury to marine mammals from piling noise’ (JNCC 2010) guidance on minimising disturbance will be followed where appropriate. Spills A Pipeline Emergency Plan will be in place for the production phase Accidental spills will be kept to a minimum through training, storage/handling procedures and good housekeeping. An OPEP will be in place for drilling and production phases. SOPEPS will be in place for all shipboard operations. Regular inspections will be undertaken to establish that all equipment is in good working order. All subsea structures will be of a fishing friendly design, of the type approved by the Subsea structures SFF. Vessel assurance process will be applied to all project vessels to ensure environmental Vessels controls are in place e.g., SOPEPS, awareness and waste management All project associated vessels will have and implement a written waste management plan compliant with the International Convention for the Prevention of Pollution from Ships (1973/1978) (MARPOL 73/78) and its Annexes. All vessels over 400 tonnes will have and maintain a Garbage Record Book During the course of operations, EnQuest will follow a hierarchy of choices when Waste dealing with contaminated fluid in order to minimise the volume discharged to sea, in line with Oil and Gas UK "Good Practice for Clean-Up Operations" document (OGUK 2006). Production water will normally be reinjected. If unavoidable, discharge will be kept to a minimum

11.4 OIL SPILL RESPONSE

The Galia field will have a site specific oil pollution emergency plan (OPEP) that meets the requirements of The Merchant Shipping (Oil Pollution Preparedness, Response Co-operation Convention) Regulations, The Offshore Installations (Emergency Pollution Control) Regulations and the latest guidance issued by the DECC. The OPEP will cover onshore and offshore responses for an incident in the Galia field. It will take into consideration drilling activities at the drill centres’, production activities on the FPSO, the production of crude oil and chemicals in the flowlines and the export of crude oil in the offloading tankers. EnQuest has subscribed to Oil Spill Response (OSR) to provide clean-up expertise and equipment in the event of oil spills. In addition, EnQuest has a contract with Petrofac to provide 24 hour emergency support, including the use of the Petrofac Emergency Response Centre (ERC). Equipped with a competent team of professionals, the ERC will be used to coordinate onshore response if required. EnQuest operates a three-tier response system.

Tier one consists of the Incident Management Team (IMT), with at least one member on call 24 hours a day, seven days a week. The IMT Duty Manager is the first responder to the ERSC.

Tier Two is the first level of the EnQuest Crisis Management Team (CMT). Mobilised by the IMT Duty Manager, the CMT sits at EnQuest’s Aberdeen office. Should an incident escalate, requiring more corporate support,

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Tier Three is activated, which consists of EnQuest’s senior leadership team, based EnQuest’s company headquarters in London (corporate HCMT, CCMT). The installed wellheads will have H4 connectors that will be compatible with the capping device built under the Well Life-Cycle Decision Framework (WLCDF) Oil and Gas UK (OGUK) initiative and now available for use.

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12 CONCLUSIONS

12.1 THE PROJECT

The field, to be renamed Galia, will be a re-development of the existing Duncan field, located within the CNS. Galia will be developed through a single production well tied-back via a new oil production flowline to the subsea Alma Production centre. It will then be produced back to the EnQuest Producer FPSO. The field is located in UKCS Blocks 30/24 in a water depth of approximately 80m, which is 280km north-east of the nearest landfall on the Northumberland coastline and 22km from the UK/Norway median line. Construction is expected to commence in August 2012, with the rig remaining on Galia for 3 months until November 2012. Field life is anticipated to be ten years. Overall, the proposed development is regarded as being a small scale oil development, in the context of other oil and gas developments in the wider CNS. Construction activities will generate a range of routine emissions/discharges to air and sea respectively, e.g;

Atmospheric emissions

Drill cuttings and water based mud discharges

Chemical discharges

Waste water and sewage discharges

Subsea noise

12.2 EXISTING ENVIRONMENT

Existing conditions at the Galia development were established through an environmental baseline and habitat assessment survey, which revealed that:

Overall, the fauna was generally uniform and moderately diverse, with some patchy low and high abundance across the survey area. The community was typical of sandy North Sea sediments. The majority of adult benthic taxa were polychaete worms. Stations sampled where historical drilling activity was prevalent were characterised by more disturbance and hydrocarbon contamination tolerant species and lower numbers of sensitive species.

One individual of Arctica islandica was identified at Station ENV9; A. islandica is listed by OSPAR (2008) as a species under threat and/or in decline in the North Sea. No habitats or species of conservation significance under the UK’s Offshore Marine Conservation (Natural Habitats, &c.) (Amendment) Regulations 2010 were observed at any other station during seabed surveys. The environmental baseline is similar to other regions of the CNS where oil and gas activity is prevalent. Meteorological conditions around the project support a dilution and dispersion regime which will rapidly reduce the impact significance of emissions to air, water and seabed (i.e., winds are sufficient to disperse atmospheric emissions, tidal currents refresh the water column within an

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estimated 1.5 hours, currents are generally sufficient to disperse drill cuttings or sediment piles on the seabed within 5 years).

12.3 POTENTIAL IMPACTS

The potential effects of the project on the environment were identified and quantified by reviewing the existing baseline environmental conditions with the potential to be affected by the project and identifying and evaluating the effect of any activities associated with the project on these conditions. It should be noted that the majority of activities were assessed as having negligible or minor residual impact on the receiving environment, with a few identified as having a residual impact of moderate significance. This ES reached the following conclusions with regards to the project’s impacts on the environment:

Benthic Environment: The total seabed footprint of the development is 0.33km2. Due to fishing activities and previous oil and gas industry activities, the benthos in the project area is typical of a moderately disturbed habitat and consequently species that inhabit the area tend to recover quickly after disturbance. The development area is sufficiently homogenous that any localised losses are unlikely to affect the integrity of the community as a whole. The placement of protective structures such as concrete mattresses will create new habitat for those species that require hard substrate for anchoring. This could lead to settlement of new species and the potential for a localised change in marine ecology. Current speeds are sufficient to erode cuttings piles and these are unlikely to persist for a long period of time. Seabed activities that cause physical disturbance have been classed as having a moderate to minor residual impact.

Protected Species: One individual of Arctica islandica was identified at Station ENV9; A. islandica is listed by OSPAR (2008) as a species under threat and/or in decline in the North Sea. At all other stations no habitats or species of conservation significance under the UK’s Offshore Marine Conservation (Natural Habitats, &c) (Amendment) Regulations 2010, which implement the requirements of the EC Habitats Directive, were observed (GEL 2011). Marine mammals are likely to be the only protected species of relevance in the Galia development. No piling will take place at Galia and therefore there is therefore a negligible risk of an offence under the Conservation (Natural Habitats &c) Regulations 1994 (as amended) and the Offshore Marine Conservation (Natural Habitats &c) Regulation 2007 (as amended in 2010).

Protected Areas: There are no protected sites within 40km of the Galia development. The nearest protected site is the Dogger Bank candidate Special Area of Conservation (cSAC) which is approximately 78km south-east from Galia. Due to the distance of the protected site from the development area, it is unlikely that there will be any impacts during normal activities.

Water/Sediment Quality: No activities were identified during construction or production that would have the potential to have a significant residual impact on water or sediment quality.

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Air Quality: Given the generally dynamic offshore environment, concentrations of NOx and SOx from construction and production activities are not expected to reach European Commission alert thresholds and there is not expected to be any residual impact on regional air quality.

Climate Change: Although identified as having a moderate impact, the emissions from Galia represent a small proportion of the total UKCS E&P contribution. Therefore it is not expected that there will be any residual impact on climate change.

Commercial Fishing and Other Marine Users: With consideration of other development activities in the CNS, safety exclusion zones are likely to have a minor impact on commercial fishing in the area as this will result in vessels being displaced from their fishing grounds. Snagging hazards will be mitigated for by using standard best practice and industry measures (i.e. use of fishing friendly structures).

Accidental Events: Spill of hydrocarbons: During construction a worst case scenario of a loss of well control would result in a release of 179,280 tonnes (214,650m3) over the 90 days it would take to mobilise and drill a relief well. As modelling with OSIS is not possible for this duration, modelling was run with a figure of 29,880 tonnes (35,775m3) of crude oil over 15 days (deemed sufficient for planning purposes). Modelling shows that depending on the prevailing wind conditions there is a 1% chance of beaching occurring on a coastline of a North Sea bordering country. Modelling also indicates that, without an intervention response, depending on the prevailing wind conditions, the spill could reach the UK coastline within 8 days and 10 hours and the Danish coastline within 5 days and 17 hours. The spill is likely to have completed dispersed within 417 days. There are numerous protected areas along the coastlines of North Sea bordering countries that could be affected by a spill (Figure 8-3). During production, a worst case scenario loss of containment of 87,000 tonnes (100,000m3) of crude oil from the export tanker was been modelled. Results are extremely similar to those seen for the loss of well control. EnQuest will have an OPEP in place to manage spill response.

Cumulative and transboundary impacts: The potential for cumulative impacts stems from both current on-going production operations and new developments. The Galia Field is in an area of extensive oil development where activities have left their mark on the seabed. Galia is a relatively small development and it is unlikely that the incremental change to seabed disturbance, produced water and atmospheric emissions is likely to substantially change the physical and biological characteristics of the region.

12.4 DECOMMISSIONING

Field life is estimated to be approximately ten years and therefore decommissioning and abandonment will occur around 2023. The arrangements for decommissioning the wells and pipelines will be developed in accordance with UK government legislation and international agreements in force at the end of field life. The potential impacts from decommissioning have not been considered in this EIA. They will be the subject of a separate EIA submitted prior to decommissioning.

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12.5 ENVIRONMENTAL MANAGEMENT

The EnQuest corporate policies and environmental management system provide a fit for purpose framework to implement the control and mitigation measures proposed in this ES. The EMS also provides adequate control and bridging arrangements for EnQuest to ensure that the contractors implement these measures. During the construction and production operations, a set of permits and consents will be obtained from the regulatory bodies. Permit conditions under these will also be fed into the EMS to ensure compliance. EMS performance will be regularly benchmarked against recommendations from independent verifications, through internal and independent audits and reviews. With mitigation measures in place, the Galia development will have a minor impact on the environment.

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13 REFERENCES

Anatec (2011). Consent to Locate - Alma (Technical Note). Prepared by Anatec on behalf of EnQuest 2nd June 2011. Reference: A2668-ENQ-CR-1 BGS (2004). Technical Report produced for Strategic Environmental Assessment – SEA2: North Sea Geology. TR_008 BSI (2001). Environmental Management - Environmental assessment of sites and organisations (EASO), Reference Number: ISO 14015: 2001 (E) Connor, D.W., Allen, J.H., Golding, N., Howell, K.L., Lieberknecht, L.M., Northern, K.O. and Reker, J.B. (2004). The Marine Habitat Classification for Britain and Ireland Version 04.05. JNCC, Peterborough ISBN 1 861 07561 8 (internet version). www.jncc.gov.uk/MarineHabitatClassification Conservation (Natural Habitats etc.) Regulations 1994 (as amended) (HR) and the Offshore Marine Conservation (Natural Habitats, etc.) Regulations 2007 (as amended in 2010) Compass Hydrographic Surveys Ltd (2004). Marine Aggregate Licence Area 430: East of Southwold Conoco Phillips (2011). http://w3.conocophillips.com/gcommon/internet/html/reports/sdreport/minimize3 _water.html Coull, K.A., Johnstone, R., and Rogers, S.I. (1998). Fisheries Sensitivity Maps for British Waters. Published and distributed by UKOOA Conservation (Natural Habitats &c) Regulations 1994 (as amended in 2010) (HR) and the Offshore Marine Conservation (Natural Habitats &c) Regulations 2007 (as amended in 2010) (OMR) DECC (2009). UK Offshore Energy Strategic Environmental Assessment. Environmental Report, January 2009. DECC (2011a) Guidance Notes on the Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) Regulations 1999 (as amended). Version 2011/0, issued October 2011 DECC (2011b). Promote UK 2011. Prospectivity of the United Kingdom (UK) Continental Shelf: North Sea Opportunities. https://www.og.decc.gov.uk/UKpromote/summary_information/North_Sea_intro _2011.pdf [Accessed February 2011] DECC (2011c). Water Production sorted by field. [Accessed March 2011] DECC Online Maritime Data GIS system. Available from http://www.maritimedata.co.uk/ [accessed June 2011] Dore, C.J., Murrells, T.P., Passant, N.R., Hobson, M.M., Thistlethwaite, G., Wagner, A., Li, Y., Bush, T., King, K.R., Norris, J., Coleman, P.J., Walker, C., Stewart, R.A., Tsagatakis, I., Conolly, C., Brophy, N.C.J. and Hann, M.R. (2008). UK Emissions of Air Pollutants 1970 to 2006. Issue 1. AEA Technology plc prepared for Defra.

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DTI (2001a). Strategic Environmental Assessment of the Mature Areas of the North Sea (SEA2). Consultation Document, H.M.S.O, London. DTI (2001b). Contaminant Status of the North Sea. Strategic Environmental Assessment - SEA2 Technical Report 004 DTI (2001c). North Sea Fish and Fisheries: Technical report produced for Strategic Environmental Assessment – SEA2. Produced by Cefas & FRS DTI (2001d). Background Information on Marine Mammals Relevant to SEA2. Technical Report 006 produced for Strategic Environmental Assessment – SEA2. Produced by Sea Mammal Research Unit (SMRU), August 2001. DTI (2001e). Human Activities in the North Sea Relevant to SEA2: Technical Report 007 - Existing activities. Produced by BMT Cordah DTI (2002). Background information on marine mammals relevant to SEA 2 and 3. Technical Report 006 to inform SEA 2 and 3. Prepared by Hammond, P.S., Gordon, J.C.D., Grellier, K., Hall, A.J., Northridge, S.P., Thompson, D., and Harwood, J. Available online http://www.offshore- sea.org.uk/consultations/SEA_3/TR_SEA3_Mammals.pdf [Accessed December 2008] DTI (2007). Meeting the Energy Challenge - A White Paper on Energy. May 2007 EnQuest (2011a) Galia Field Development Plan Licence P1825. ENQ-KN501- PM-000-BOD-0003. DECC Reference D/4110/2011 EnQuest (2011b). Ardmore Redevelopment Project HSE Plan. Document No. ENQ-KNI-HS-000-PLA-0001 EnQuest (2012). Knightsbridge Project: Alma & Galia Field Development Basis of Design. Document No. ENQ-KN501-PM-000-BOD-0002 Revision B3 European Commission (1999). Guidelines for the Assessment of Indirect and Cumulative Impacts as well as Impact Interactions. EC DG XI Environment, Nuclear Safety & Civil Protection. May 1999. Produced by Hyder. Flemming, N.C. (2002). The scope of Strategic Environmental Assessment of North Sea areas SEA3 and SEA2 in regard to prehistoric archaeological remains. August 202 Report prepared for the DTI SEA3_TR014 Gardline Geosurvey Limited (2011). Galia Site Survey UKCS 30/24. Ref 8826.1 Gardline Geosurvey Limited (2011). UKCS Blocks 30/24, 30/25, 30/29 and 30/30 Alma Field Development December 2010 to January 2011 Survey report Gardline Environmental (2011). Galia Sites and Pipeline Route Surveys UKCS 30/24 and 30/25: Environmental Baseline Report. Ref 8826.5 Gardline Environmental (2011). Alma Field Development Site Survey: Environmental Baseline & Habitat Assessment Survey. Ref 8602 Gaz de France Britain (2005). Cygnus Exploration Well Environmental Statement. DECC Project Reference No.: W/2880/2005. HM Government (2009). The UK Low Carbon Transition Policy. National strategy for climate and energy. 15th July 2009

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JNCC (2010). The protection of marine European Protected Species from injury and disturbance. Guidance for the marine area in England and Wales and the UK offshore marine area. Prepared by JNCC (June 2010). JNCC (2011). http://www.jncc.gov.uk/page-4535#DoggerBank [accessed 08/02/2011] JNCC (2012). SACs with Marine Components. Joint Nature Conservation Committee. Available at http;//jncc.defra.gov.uk/page-1445. Accessed April 2012. Johnston, C.M., Turnbull, C.G. and Tasker, M.L. (2004). Natura in UK Offshore waters: Advice to support the implementation of the EC Habitats and Birds Directive in UK Offshore waters. JNCC 04 P23 KISCA (2010). GIS data, last downloaded February 2010 Law, R.J., Waldock, M.J., Allchin, C.R., Laslett, R.E. and Bailey, K.J. (1994). Contaminants in seawater around England and Wales: Results from monitoring surveys, 1990-1992. Mar. Pollut. Bull., 28: 668-675 Marine Aggregate Licence Area 430: East of Southwold, Compass Hydrographic Surveys Ltd 2004) MMO (2010). 2004 – 2010 landings data for ICES rectangles 41F2 MCA (2011). http://www.dft.gov.uk/mca/ Met Office (2011). Met Office European model (56.0°N 3.14°E Jan 1998 - Nov 2008) Net Gain (2011). Net Gain Final Recommendations Submission to Natural England & JNCC http://www.netgainmcz.org/docs/Net_Gain_Final_Rec_v1_1.pdf OGUK (2006). Good practice for cleanup in well operations. Revision 1. Oil and Gas UK Environmental Legislation website: Well Clean-up OGUK (2008). Environmental Legislation Website. The Statutory Regime. Web page updated 29 October 2008. [Accessed November 2008] OGUK (2009). EEMS Atmospheric Reporting Data 1.0 - Facility Emissions (Reporting Year 2008) OGUK (2010). EEMS Atmospheric Reporting Data 1.0 - Facility Emissions (Reporting Year 2009) OGUK (2011) EEMS Atmospheric Reporting Data 1.0 - Facility Emissions (Reporting Year 2010) Olsgard, F. and Gray, J.S., (1995). A comprehensive analysis of the effects of offshore oil and gas exploration and production on the benthic communities of the Norwegian continental shelf. Marine Ecology Progress Series, 122: 277-306 OSPAR (2008)

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OSPAR Commission (2000). Quality Status Report 2000. OSPAR Commission, London. 136 + xiii pp Available online http://www.ospar.org/content/content.asp?menu=00790830300000_000000_00 0000 [Accessed January 2009] OSPAR Commission (2010). Quality Status Report 2010 for the North-East OSR (2011). Oil Spill Modelling for Alma Field Development. Prepared for Metoc Ltd. Project Number 4558 Reid, J.B., Evans, P.G.H. and Northridge, S.P. (2003). Atlas of Cetacean distribution in northwest European waters. Joint Nature Conservation Committee, Peterborough, UK Richardson, W.J., Thomson, D.H., Green Jr, C.R. and Malme, C.I. (1995). Marine mammals and noise. Academic Press, New York RYA (2008). UK Coastal Atlas of Recreational Boating. Recreational Cruising Routes, Sailing and Racing Areas around the UK Coast. Second Edition Sadler, B. and McCabe, M (Eds) (2002). United Nations Environmental Programme (UNEP) EIA Training Resources Manual, Second Edition. http://eia.unu.edu SCANS-II (2008). Small Cetaceans in the European Atlantic and North Sea. Final Report submitted to the European Commission under project LIFE04NAT/GB/000245. Available from SMRU, Gatty Marine Laboratory, University of St Andrews, St Andrews, Fife, KY16 8LB, UK Skov, H., Durinck, J., Leopold, M.F., and Tasker, M.L. (1995). Important Bird Areas for seabirds in the North Sea. BirdLife International, Cambridge Stone, C.J., Webb, A., Barton, C., Ratcliff, N., Reed, T.C., Tasker, M., Camphuysen, C. J. and Pienkowski, M.W. (1995). An atlas of seabird distribution in the north-west European waters. Joint Nature Conservation Committee, Peterborough Stone, C.J. (2003). The effects of seismic activity on marine mammals in UK waters, 1998-2000. JNCC Report No. 323. Joint Nature Conservation Committee, Peterborough, UK The Crown Estate (2011). The Crown Estate Thomas and Thistlethwaite (2008). Greenhouse Gas Emissions Data for International Aviation and Shipping, 1990-2006. Published 29/10/2008 for the National Atmospheric Emissions Inventory http://naei.defra.gov.uk/reports.php?list=AP UK Climate Impact Programme (2002). UKCIP02 Climate Change scenarios gateway. UK Deal (2010). GIS data, last downloaded November 2010 UK National Air Quality Archive (2009). http://laqm.defra.gov.uk/maps/maps2008.html UK National Air Quality Archive (2011). http://uk-air.defra.gov.uk/

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UK Policy Planning Statement 25: Development and Flood Risk. Revised March 2010 (CLG 2010) UK Climate Impacts Programme (UKCIP) website (http://www.ukcip.org.uk/) (2011) UKCP (2009). UK climate change predictions http://ukclimateprojections.defra.gov.uk/content/view/2013/500/ UKMMAS (2010). Charting Progress 2 - The State of UK Seas. http://chartingprogress.defra.gov.uk/ UKOOA (1999). Drill Cuttings Initiative, Research and Development Programme. Activity 2.1. Faunal Colonisation of Drill Cuttings Pile Based on Literature Review. United Kingdom Offshore Operators Association, Aberdeen, UK UNFCCC (2008). United Nations Framework Convention on Climate Change (1994). http://unfccc.int/essential_background/convention/items/2627.php Wessex Archaeology 2008). Marine Class Descriptions and Principles of Selection in Aggregate Areas. EH Project Number 5383. Ref: 67040.02. Issued February 2008

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Appendix A Environmental Impact Assessment

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A.1 Interaction Matrix

Environmental Receptor Physical Biological Human Plankton Seabirds Shipping Shipping Air quality Air quality and species and species Archaeology Archaeology Climate change change Climate Water resources Water resources Marine mammals Marine mammals Fish and shellfish Seabed conditions Other marine users users marine Other Commercial fisheries fisheries Commercial Benthic communities Project Activity Marine protected sites General Construction Physical presence and movement of vessels Bulk storage and transfer Drilling of wells Installation of flowlines Production Operation and maintenance of FPSO Increased movement of export tanker and supply vessels Flaring during initial stages of production Presence of subsea infrastructure Accidental Events Overboard loss of equipment or waste Chemical / hydrocarbon release (< 1 tonne) Chemical / hydrocarbon release (1-10 tonnes) Chemical / hydrocarbon release (> 10 tonnes) Notes: 1) Interactions associated with the presence of the FPSO or shuttle tanker are ignored (since already present for Alma). 2) Accidental events during production are associated with Galia subsea infrastructure and a small increase in frequency of movement of shuttle tanker. Galia tie back would not be expected to have a significant impact on incident frequency on the FPSO

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A.2 Construction

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

A – Air Quality A-1 Physical Exhaust gas Localised Ensure all machinery is maintained. Atmospheric emissions from exhaust gases will be low (Section 5.5).

presence and emissions deterioration in y Use of cleaner low emission fuels. Pollutants will be dispersed and diluted to levels below health and ible ible movement of air quality environmental guidelines within 500m of the discharge point. See Section r g likel li Stack heights in accordance with the y

vessels g 7.1 for full discussion. relevant regulations. Ne Ver N ------7.1 Drilling of wells Mino A-2 Bulk storage Dust release Localised Ensure all machinery used for transfers Dust released from the bulk transfer/storage of chemicals and/or cements and transfer during transfer deterioration in is regularly cleaned and maintained. will be low (Section 5.2). Any dust released into the atmosphere will disperse ible ible

r air quality g and settle on the sea surface around the rig where it will quickly disperse y li g through the water column. As the amount of dust released will be minimal, N ------7.1 Likel Ne Mino no residual impact on air quality is envisaged. B - Climate Change

B-1 Physical Exhaust gas Loading of Ensure all machinery is maintained. Approximately 15,153 tonnes of CO2 (e) will be emitted during construction

presence and emissions greenhouse y (Section 5.5.1). As a comparison the annual emissions represent 0.31% of ible ible

r movement of gases e.g., g UK emissions from similar offshore activities in 2009. This is a relatively likel li y vessels CO2, CH4, g small contributor to annual UK emissions and is typical for a standard oil N ------7.2 Ver Ne Mino development of this size. See Section 7.2 for full discussion. C - Water Resource C-1 Physical Discharge of Localised Every vessel will have and implement a It is estimated that a maximum of 16,937m3 of sewage and grey water will presence and sewage, grey deterioration in written waste management plan, be discharged to sea from construction vessels (Section 5.5.2). Given the movement of water, food water quality compliant with MARPOL 73/78. prevalent metocean conditions in the project area (e.g., winds, waves, tides vessels waste and Annex V (Garbage) is particularly and currents), the short-time scale of the construction period and the small drainage relevant. No plastics/plastic containing cumulative volume of discharges, the marine environment will be able to water material will be disposed of at sea, rapidly assimilate the discharges through natural bacterial action. regardless of location. Paper & food Considering the active mitigation in place it is likely that any degradation in

water quality will be transient (limited to a few hours after the discharge) and

y wastes will only be discharged outside there will not be any residual impacts on water quality. ible ible the 12nm limit. r g Likel li y g General household products will be N ------7.3 Ver Ne Mino selected that are environmentally benign.

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Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

C-2 Bulk storage Dust release Localised Ensure all machinery used for transfers Dust released from the bulk transfer/storage of chemicals and/or cements and transfer during transfer deterioration in is regularly cleaned and maintained. will be small (Section 5.2). Any dust released into the atmosphere will water quality disperse and settle on the sea surface around the rig where it will quickly ible ible

r g disperse through the water column. Any degradation in water quality will be li g transient (limited to a few hours after the discharge) and it is unlikely that Possible Ne N ------7.3 Mino there will be any residual impacts on water quality. C-3 Drilling of wells Discharge of Localised Daily recording of chemical use to allow All discharges will be risk assessed and be within permitted levels. Currents -1 Installation of chemicals deterioration in more refined and efficient use. in the project area are of average strength for the CNS (0.2ms ) and flowlines (including water quality Where possible chemicals will be combined with wave action will disperse and dilute chemical discharges WBM) during construction. Currents will refresh a 500m radius column of water recycled, skipped and shipped or re- injected and not discharged. surrounding the discharge location within one and a half hours (Section 7.3). No lasting effect on water quality is expected. Selections of chemicals will be made in accordance with the CEFAS ranked list, where chemicals ranked as lower potential hazards are preferentially chosen. Only chemicals permitted through the relevant Offshore Chemicals

y Regulations chemical permit (i.e. ible ible

r g PON15B or PON15C) and that have Likel li y g been subject to a risk assessment will be N ------7.3 Ver Ne Mino discharged. C-4 Drilling of wells Discharge of Localised All discharges will be covered by an All discharges will be within permitted levels and visibly oily contaminated reservoir deterioration in approved OPPC permit. fluids will not be discharged. Currents in the project area are of average -1 hydrocarbons water quality Visibly oily contaminated fluids will not be strength for the CNS (0.2ms ) and combined with wave action will disperse ible ible

r g reservoir hydrocarbons during drilling. Currents will refresh a 500m radius

li discharged. g column of water surrounding the discharge location within one and a half N ------7.3 Possible Ne Mino hours (Section 7.3). No lasting effect on water quality is expected.

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Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

C-5 Installation of Concrete Increased No mitigation envisaged. A maximum of 2,700m2 of seabed will be covered by concrete mattresses. flowlines mattressing suspended As the material is placed on the seabed, sediments will be displaced and sediment loads suspended. Sediment particle analysis indicates that sediments are & turbidity predominantly sand, which will quickly fall out of suspension due to its weight. The silt content is negligible and there is unlikely to be a significant

y increase in suspended sediment loads in the water column. In addition, the ible ible

r g impact occurs against a background of seabed disturbance as a result of Likel li y g wave and tidal activity. The impact will be localised and very short-term in Ver N ------7.3 Ne Mino terms of effects on water quality. C-6 Installation of Trenching Increased The impact will be minimised through As the flowlines will be trenched into the seabed, sediments will be flowlines and backfill suspended careful route design. displaced and suspended. Sediment particle analysis indicates that sediment loads sediments are predominantly sand, which will quickly fall out of suspension. & turbidity The silt content is negligible and there is unlikely to be a significant increase

y in suspended sediment loads in the water column. In addition, the impact ible ible

r g occurs against a background of seabed disturbance as a result of wave and Likel li y g tidal activity. The impact will be localised and very short-term in terms of N ------7.3 Ver Ne Mino effects on water quality. C-7 Installation of Physical Increased No mitigation envisaged. As per Section C-6, as the well head is placed on the seabed, sediments will flow lines and presence of suspended be displaced and suspended. The impact will be localised and very short- ible ible subsea subsea sediment loads term in terms of effects on water quality. r g li

infrastructure infrastructure & turbidity g N ------7.3 Possible Possible Ne Mino

D -Seabed conditions D-1 Physical Anchoring Disaggregation The footprint of the anchors will be A total of 8 anchors will be deployed within a 1,500m radius of the rig at the presence and of surface minimised. drill site. The total area of seabed impacted by all anchors and chains has movement of sediments been estimated at 2,600m2. Anchor mounds are common where seabed vessels sediments or shallow sub-surface sediments are composed of clay and are expected to persist for ten years or more. The Galia development area comprises a <2m thickness of very loose to loose silty shelly sands (with a varying degree of gravel and shells) over firm

y to very stiff sandy gravelly clay. When retrieved, the anchors are expected ible ible to leave a small area of residual disturbance. r g Likel li y g However, the area impacted is minor when compared to the extent of the Y Likely Moderate Local Low Short Minor 7.4 Ver Ne Mino CNS and physical disturbance from other activities such as trawling.

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Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

D-2 Drilling of wells Discharge of Change in No mitigation envisaged All discharged cuttings will be incorporated in the sediment through cuttings seabed bioturbation and general sediment mobility. Significant erosion of cuttings

topography y piles starts when the seabed critical velocity reaches 0.35ms-1 (UKOOA ible ible -1 r g 1999). Peak seabed currents (0.42ms ) will ensure that all cuttings piles will Likel li y g eventually disperse, although there is the possibility that they may persist for Ver Y Likely Moderate Local Low Short Minor 7.4 Ne Mino a number of years. D-3 Drilling of wells Discharge of Sediment As per Section C-3 All discharges will be risk assessed and will be within permitted levels. Only Installation of chemicals contamination chemicals discharged at the seabed will have a direct impact on sediments. flowlines (including No discharge of OBM is permitted so levels of contamination are not WBM) expected to rise over existing historical levels. Barite and bentonite present in the WBM can contaminate sediments and be noticeable in sampling for up to 10 years after discharge. However due to the historical use of the area for oil and gas development it is unlikely that this will be a noticeable increase.

-1 y Currents in the project area are of average strength for the CNS (0.2ms ) ible ible and combined with wave action will disperse and dilute chemical discharges r g Likel li y

g during construction. Currents will refresh a 500m radius column of water Y Very Likely Moderate Local Low Short Minor 7.4 Ver Ne Mino surrounding the discharge location within one and a half hours (Section 7.3). D-4 Drilling of wells Discharge of Sediment As per Section C-4 All discharges of fluids potentially contaminated with hydrocarbons will be reservoir contamination within permitted levels and visibly oily contaminated fluids will not be hydrocarbons discharged. It is unlikely that contamination will reach the seabed as discharge will be at the sea surface and currents will refresh a 500m radius column of water surrounding the discharge location within one and a half hours (Section 7.3). However should it reach the seabed then given the

y ible ible

r g previous use of the area for oil and gas development, levels of hydrocarbon li g contamination are not expected to rise over existing historical levels. N ------7.4 Unlikel Mino Ne

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Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

D-5 Installation of Physical Compaction The footprint of any structure will be The wellhead will have a footprint on the seabed of 81m2. All surface flowlines and presence of and minimised. sediment within this footprint will be unavailable for future colonisation. subsea subsea disaggregation However, sediments in the surrounding area are not particularly sensitive. In infrastructure infrastructure of surface addition, the area impacted is minor when compared to the extent of the and flowlines sediments CNS and physical disturbance from other activities such as trawling. As the flowlines are to be trenched directly into the seabed, this area of

y seabed will be disturbed but will then be available for colonisation purposes. ible ible

r g Sediments in the area are not particularly sensitive and the impact will be Likel li y g localised. There will be no change in sediment composition and no Y Very Likely Moderate Local Low Short Minor 7.4 Ver Ne Mino contamination, therefore no long-term effects on sediments is envisaged. D-6 Installation of Trenching Change in The impact will be minimised through Trenching will have a total seabed footprint of 0.33km2 for all three trenches. flowlines and backfill surface careful route design. Sediments in the surrounding area are not particularly sensitive; however sediments use of the trenching system will bring sediments from deeper lithologies to Change in the surface. Whilst this will disturb the sediments, there will not be a topography significant change. Although the trenching methodology will create berms or leading to spoil piles, there is unlikely to be an affect on sediment transport pathways changes in as they will be smoothed off and reduced in size as the plough passes over ible ible them. In addition, the area impacted is minor when compared to the extent

r sediment g y li transport g of the CNS and physical disturbance from other activities such as trawling. Y Possible Moderate Local Low Short Minor 7.4 Likel Ne pathways Mino D-7 Installation of Concrete Change in The footprint of any protective structures When the concrete mattresses are placed on the seabed, they will have a ible ible

3

flowlines mattressing seabed r will be minimised maximum footprint of 2,700m . A slightly raised profile may mean that g y

li topography g deposition or scour occur around mattresses. Y Possible Moderate Local Low Short Minor 7.4 Likel Ne Mino

E – Plankton E-1 Physical Discharge of Organic As per Section C1 Cumulative discharge volumes will be very small and combined with the fact presence and sewage, grey enrichment that drilling rigs will not be on permanent location it is unlikely that any movement of water, food leading to discharges will lead to any measurable organic enrichment. vessels waste and raised biological

drainage oxygen y ible ible

r water demand. May g Likel li y change balance g N ------8.1 Ver Ne of food chain. Mino

REPORT REF: GALIA ES D/4127/2011 A-7 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

E-2 Drilling of wells Discharge of Potential toxic As per Section C3 All discharges will be risk assessed and be within permitted levels. Installation of chemicals effects Although sensitive to changes in water quality, the plankton community flowlines (including undergoes a continual change in individuals with those from the surrounding

WBM)

y waters and therefore has extremely rapid recovery rates. ible ible

r g As per section C-3, discharged chemicals will not be present within the Likel li y g water column for long enough or at high enough concentrations to pose a Ver N ------8.1 Ne Mino significant threat to plankton. E-3 Drilling of wells Discharge of Potential toxic As per Section C-4 As per Section C-4. No lasting effect on plankton is expected. ible ible

r reservoir effects g li hydrocarbons g N ------8.1 Possible Ne Mino

F - Benthic communities F-1 Physical Anchoring Physical The footprint of the anchors will be As per Section D-1. Within the impact area sessile species will be killed. presence and damage to minimised The benthic community within the project area is typical for the CNS with no

movement of individuals y rare or protected species identified in the site surveys. Following removal of ible ible

r vessels g the anchors, recolonisation and recovery to pre—impact levels is likely to Likel Smothering li y g take place through immigration into the disturbed area over a period of one Y Likely Moderate Local Low Short Minor 8.2 Ver Ne Mino to five years.

REPORT REF: GALIA ES D/4127/2011 A-8 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

F-2 Drilling of wells Discharge of Physical No mitigation envisaged Cuttings discharged at the seabed will have a direct impact on the benthic cuttings damage to community. Cuttings discharged through the water column could have an individuals impact on the benthic community as they settle out on the seabed. Smothering There will be a direct loss of any species on the seabed underneath the cuttings piles generated by drilling. However this will be localised and minor when compared to the extent of the CNS and physical disturbance from other activities such as trawling. Cuttings will be incorporated in the sediment through bioturbation and general sediment mobility. Significant erosion of cuttings piles starts when the seabed critical velocity reaches 0.35ms-1 (UKOOA 1999). Seabed currents (0.42ms-1) will ensure that all cuttings piles will disperse quickly, although there is the possibility that they may persist for a number of years. Experience in the CNS region indicates that cuttings piles will persist for 5- 10 years.

y As such, benthic communities underneath the cuttings piles will be directly ible ible

r g impacted however, due to the small scale and significant erosion potential of Likel li y g the surrounding region, a minor impact on benthic communities is Y Very Likely Moderate Local Low Moderate Minor 8.2 Ver Ne Mino anticipated. F-3 Drilling of wells Discharge of Potential toxic As per Section C-3 As per Section D-3. Components of the WBM e.g., barite and bentonite, are Installation of chemicals effects known to contaminate seabed sediments; the effects of which may be flowlines (including noticeable for 10 years after drilling has ceased. However, this does not WBM) impede the recolonisation of an area disturbed by drill cuttings and WBM. Small quantities of inhibition chemicals such as biocide and oxygen

y scavenger used in flowline commissioning will be discharged at seabed ible ible

r level. Any toxic impacts on benthic communities will be extremely localised, g Likel li y g restricted to the immediate area surrounding the discharge location and as Y Very Likely Moderate Local Low Short Minor 8.2 Ver Ne Mino such are unlikely to have a noticeable effect above individual level. F-4 Drilling of wells Discharge of Potential toxic As per Section C-4 As per Section D-4. Discharges will be at the sea surface in 80m water ible ible reservoir effects depth. The small quantity of oil to be discharged will have dispersed and r g li

hydrocarbons g diluted to below toxic levels and it is not expected will have an impact on N ------8.2 Possible Possible Ne Mino benthic communities.

REPORT REF: GALIA ES D/4127/2011 A-9 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

F-5 Installation of Physical Habitat loss The footprint of any structure will be As per Section D-5. flowlines presence of Physical minimised Sessile species in the impact footprint will be killed. The benthic community subsea damage to is typical of the CNS with no rare or protected species identified in the site infrastructure individuals surveys. The presence of subsea infrastructure will create new habitat for

Concrete Smothering y those species that require hard substrate for anchoring, but it may take ible ible mattressing longer to establish a community due to the lack of larvae or adult sources in r g Likel li

Habitat creation y g the surrounding area. Minor Minor 8.2 Ver Y Very Likely Moderate Local Low Short Ne Mino

F-6 Installation of Trenching Habitat loss The impact will be minimised through The disturbance of sediments may cause some fatalities of infauna, flowlines and backfill careful route design. although this will be limited to the width of the area of disturbance

Physical damage to y (approximately 20m). The deposition of suspended sediments may ible ible

r g smother sessile species and filter-feeders along the pipeline corridor, but the Likel individuals li y g extent of this impact will be limited and the intensity of the impact will Y Very Likely Moderate Local Low Short Minor 8.2 Ver Ne Smothering Mino decrease with distance from the flowline. G - Fish and shellfish G-1 Physical Anchoring Loss or The footprint of the anchors will be The footprint of anchor mounds and chains is not expected to significantly presence and disturbance of minimised. affect fish communities. movement of spawning and There is a possibility that pelagic fish species could collide with the anchor vessels nursery chains and become entangled whilst the drilling rig is on station. There is no grounds mitigation envisaged for this potential impact as it is a very minor risk. ible ible effecting stock r g

li

viability g Y Unlikely Short Local Low Short Minor 8.3 Possible Possible Ne Collision risk Mino

REPORT REF: GALIA ES D/4127/2011 A-10 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

G-2 Physical Discharge of Organic As per Section C-1 Considering the active mitigation in place it is likely that any deterioration in presence and sewage, grey enrichment fish or shellfish will be transient. It is very unlikely that there will be any movement of water, food leading to residual impacts. vessels waste and raised biological drainage oxygen water demand. May increase plankton & fish

populations y ible ible

r changing g Likel li y balance of food g N ------8.3 Ver Ne chain Mino G-3 Physical Subsea noise Disturbance No mitigation envisaged As the majority of the noise generated by offshore oil installations is low presence and causing frequency (<1kHz), any impact is likely to be minimal. No piling will be movement of avoidance of undertaken at Galia and therefore it is very unlikely that there will be any vessels spawning & residual impacts. nursery grounds ible ible

r Physical g li damage to g N ------8.3 Possible Possible Ne individuals Mino G-4 Drilling of wells Discharge of Loss of No mitigation envisaged The impact on individual species is expected to be negligible, although cuttings spawning & demersal species could be affected through temporary disturbance or nursery ground habitat around drill centres. The deposition of drill cuttings on the seabed

effecting stock has the potential to change the sediment so that it is no longer preferential viability y as a spawning habitat. However, the area affected is extremely small when

compared to the size of the spawning and nursery grounds used in the

Physical r Unlikel damage to y North Sea and any slight changes to spawning habits this might cause will Y Very Unlikely Moderate Local Low Moderate Minor 8.3 Ver individuals Low Mino not affect stock recruitment or population viability.

REPORT REF: GALIA ES D/4127/2011 A-11 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

G-5 Drilling of wells Discharge of Potential toxic As per Section C-3 During drilling and pipeline installation a variety of chemicals will be used. Installation of chemicals effects The majority of chemicals to be used are classified OCNS category E or flowlines (including Gold and therefore pose little risk to the marine environment. In some cases WBM) it will be necessary to use chemicals which have a lower environmental

y performance, with high toxicity, low biodegradation or the potential to ible ible

r g bioaccumulate. Conditions in the vicinity of the development are such that Likel li y g any discharge will be quickly dispersed and therefore exposure of fish and Ver N ------8.3 Ne Mino shellfish to these chemicals will be reduced. G-6 Drilling of wells Discharge of Potential toxic As per Section C-4 Discharges will be from the rig and will be rapidly dispersed and dissipated.

y ible ible

reservoir effects r It is unlikely that the small volumes discharged will be present in the water g li

hydrocarbons g column for sufficient periods to pose a risk of toxic potential to fish species. N ------8.3 Unlikel Mino Ne

G-7 Installation of Physical Loss of The footprint of any structure will be Although activities will result in a loss of some spawning and nursery flowlines presence of spawning & minimised grounds, the development site makes up only a small percentage of the subsea nursery ground total spawning and nursery areas for these species in the North Sea. infrastructure effecting stock Therefore the impact on fish populations is expected to be minimal. viability

y

Physical r damage to N ------8.3 Unlikel individuals Low Mino G-8 Installation of Trenching Loss of The impact will be minimised through The development is within the spawning and nursery grounds for five flowlines and backfill spawning & careful route design. species. However, trenching will only disturb a relatively small area of nursery ground seabed (in comparison to the wider CNS spawning and nursery grounds) effecting stock and will not change the sediment composition. Species will be able to use viability the area again during the next season. Therefore the impact on fish ible ible populations is expected to be minimal. r Physical g li damage to g N ------8.3 Possible Possible Ne individuals Mino

REPORT REF: GALIA ES D/4127/2011 A-12 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

G-9 Installation of Concrete Loss of The footprint of any protective structures Using only the necessary amount of material will help mitigate against flowlines mattressing spawning & will be minimised unnecessary habitat loss. Although activities will result in a loss of some nursery ground spawning and nursery grounds, the development site makes up only a small Physical percentage of the total spawning and nursery areas for these species in the ible ible North Sea. Therefore the impact on fish populations is expected to be r damage to g li individuals g minimal. The presence of hard substrate may attract new species to the Possible Ne N ------8.3 Mino area. H - Seabirds H-1 Physical Increased Localised No mitigation envisaged It is possible that seabirds resting on the sea surface could be disturbed by presence and vessel activity disturbance of the presence of the drilling rig and support vessels. However, this is not ible ible movement of in region seabirds from considered to be a significant threat to seabirds due to the existing level of r g li

vessels the sea surface g shipping activity in the area. N ------8.4 Possible Possible Ne Mino

H-2 Drilling of wells Discharge of Potential toxic y As per Section C-3 Discharged materials will not be present within the water column for long chemicals effect enough or at high enough concentrations to pose a significant threat to the

Installation of ible nificant nificant g Unlikel

(including li seabird community. g y

flowlines g WBM) N ------8.4 Ver Ne Insi

H-3 Drilling of wells Discharge of Potential toxic As per Section C-4 Discharges will be from the rig and will be rapidly dispersed and dissipated.

reservoir effect It is unlikely that the small volumes discharged will be present in the water

y hydrocarbons column for sufficient periods to pose a risk to seabirds. ible ible nificant nificant g Unlikel li g y g N ------8.4 Ver Ne Insi

I - Marine mammals

REPORT REF: GALIA ES D/4127/2011 A-13 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

I-1 Physical Subsea noise Can cause JNCC guidelines (JNCC 2010) on ‘The The majority of subsea noise source levels generated by construction presence and physical injury protection of marine European Protected activities are generally below 180dB. High noise levels during rig move movement of or disturbance Species from Injury and Disturbance’ will activities have been recorded north of Scotland (Swift and Thompson 2000). vessels be followed. Many marine mammals exhibit overt behavioural reactions at a received noise level of 120dB for continuous noise, such as drilling. Noise levels in excess of 120dB may be tolerated for a period of time, but the likelihood of behavioural response increases. Prolonged sound could result in marine mammals moving away from preferred areas. However, there is no definitive data to suggest that construction noise could adversely affect small cetaceans. It is an offence under the EC Habitats Directive to cause physical injury or to deliberately disturb wild animals of an EPS. The eight cetacean species

r which are observed in the project area are all considered EPS. No piling will be undertaken at Galia and therefore it is very unlikely that there will be any N ------8.5 Possible Possible Low Mino residual impacts. I-2 Physical Anchoring Collision risk No mitigation envisaged. It is possible that marine mammals could collide with the anchor chains

y ible ible presence and used to hold the drilling rig in position. However this is not considered to be a r g li

movement of g significant threat to marine mammals as marine mammals should be able to N ------8.5 Unlikel Mino vessels Ne detect and avoid the chains. I-3 Physical Discharge of Feeding As per Section C-1 C-1 concluded that there is not expected to be a residual impact on water presence and sewage, grey impairment due quality. Therefore, it is unlikely that marine mammals will be affected by the movement of water, food to organic discharge of sewage, grey water, food waste and drainage water. vessels waste and enrichment ible ible nificant nificant drainage effecting g li g water balance of food g N ------8.5 Possible Ne chain Insi I-4 Drilling of wells Discharge of Potential toxic As per Section C-3 During drilling and pipeline installation a variety of chemicals will be used. Installation of chemicals effect The majority of chemicals to be used are classified OCNS category E or HQ flowlines colour band Gold and therefore pose little risk to the marine environment. In

y some cases it will be necessary to use chemicals which have a lower environmental performance, with high toxicity, low biodegradation or the ible ible nificant nificant g potential to bioaccumulate. Conditions in the vicinity of the development are Unlikel li g y g such that any discharge will be quickly dispersed and therefore exposure of N ------8.5 Ver Ne Insi marine mammals to these chemicals will be reduced.

REPORT REF: GALIA ES D/4127/2011 A-14 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

I-5 Drilling of wells Discharge of Potential toxic y As per Section C-4 Discharges will be from the rig and will be rapidly dispersed and dissipated. reservoir effect It is unlikely that the small volumes discharged will be present in the water ible ible nificant nificant hydrocarbons g column for sufficient periods to pose a risk of toxic potential to marine Unlikel li g y g mammals. Ver N ------8.5 Ne Insi

J- Marine protected sites and species

J-1 Physical Anchoring Could affect y No mitigation envisaged. There are no marine protected areas within 40km. The nearest protected presence and integrity of site is the Dogger Bank candidate Special Area of Conservation (cSAC) ible ible nificant nificant movement of protected site g which is approximately 78km south-east from the Galia drill centre. Due to Unlikel li g y vessels g the distance of the protected site from the development area, it is unlikely N ------8.6 Ver Ne Insi that there will be any impacts. J-2 Physical Subsea noise Can cause As per Section I-1 Eight species of cetacean are known to frequent the project area at certain presence and physical injury times of the year. All cetaceans are EPS. Section I-1 concluded that there

movement of or disturbance will be no residual impact on marine mammals. vessels to protected r N ------8.6 Drilling of wells species Possible Low Mino J-3 Physical Discharge of Potential toxic As per Section C-1 Eight species of cetacean are known to frequent the project area at certain presence and sewage, grey effects on times of the year. All cetaceans are EPS. The impact on marine mammals movement of water, food protected was assessed in I-3. ible ible

r vessels waste and species g li drainage g N ------8.6 Possible Possible Ne water Mino

J-4 Drilling of wells Discharge of Could affect y No mitigation envisaged. As there are no protected areas within 40km, no lasting effect on protected cuttings integrity of sites is expected. ible ible nificant nificant

protected site g Unlikel

li g y g N ------8.6 Ver Ne Insi

J-5 Drilling of wells Discharge of Potential toxic y As per Section C-3 Eight species of cetacean are known to frequent the project area at certain Installation of chemicals effect on times of the year. All cetaceans are EPS The impact on marine mammals ible ible nificant nificant g

(including protected Unlikel was assessed in I-4. li g

flowlines y WBM) species g N ------8.6 Ver Ne Insi

REPORT REF: GALIA ES D/4127/2011 A-15 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

J-6 Drilling of wells Discharge of Potential toxic y As per Section C-4 Discharges will be from the rig and will be rapidly dispersed and dissipated. reservoir effect on It is unlikely that the small volumes discharged will be present in the water ible ible nificant nificant g

hydrocarbons protected Unlikel column for sufficient periods to pose a risk of toxic potential to any protected li g y species g species. Ver N ------8.6 Ne Insi

J-7 Installation of Physical Could affect No mitigation envisaged. As there are no protected areas within 40km, no lasting effect on protected y flowlines presence of integrity of sites is expected. ible ible nificant nificant

subsea protected site g Unlikel

li g y infrastructure g N ------8.6 Ver Ne and flowlines Insi

J-8 Installation of Concrete Could affect y No mitigation envisaged. As there are no protected areas within 40km, no lasting effect on protected flowlines mattressing integrity of sites is expected. ible ible nificant nificant protected site g Unlikel li

g y g N ------8.6 Ver Ne Insi

J-9 Installation of Trenching Could affect No mitigation envisaged. As there are no protected areas within 40km, no lasting effect on protected y flowlines and backfill integrity of sites is expected.

protected site ible nificant nificant g

Unlikel Any suspended sediments from trenching are unlikely to travel far enough to li g y g have a impact on protected sites outside of 40km. N ------8.6 Ver Ne Insi

K - Commercial fisheries K-1 Physical Increased Exclusion from A 500m safety exclusion zone will be Fishing vessels will be excluded from the safety zone around the drilling rig presence and vessel activity fishing grounds enforced around the drilling rig at all for approximately 90 days. A 500m safety exclusion zone will also be in movement of in region Potential times. place along the flowline route as the flowlines are installed. vessels Safety collision risk The drilling rig and construction vessels The Galia development area is not considered to be a commercially exclusion will be appropriately lit and sound important ground for pelagic and demersal species. An average of 125 zones warnings will be broadcast in poor tonnes of fish and shellfish, worth approximately £115,703 are landed each visibility. year from the ICES rectangle (41F2) that covers the development area. Users of the sea will be notified of the The exclusion area (0.8km2) is small in comparison to the wider ICES Block

y presence and intended movements of (3,086km2), however, fishing vessels will have to relocate and therefore it is ible ible

r g construction vessels via the Kingfisher concluded that there will be a minor residual impact. Likel li y g fortnightly bulletins, Notices to Mariners Y Very Likely Moderate Local Low Short Minor 9.1 Ver Ne Mino and VHF radio broadcast.

REPORT REF: GALIA ES D/4127/2011 A-16 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

K-2 Physical Anchoring Anchor mounds The footprint of the anchors will be Anchor mounds are a common feature of the North Sea around oil and gas ible ible

r presence and could snag g minimised development areas. Seabed imagery of areas where anchoring has li movement of fishing gear g occurred in the past often shows the area criss-crossed by trawl marks. Possible Ne Y Possible Moderate Local Low Short Minor 9.1 vessels Mino K-3 Drilling of wells Discharge of Could snag None envisaged All cuttings piles will be within the 500m radius safety exclusion zones cuttings fishing gear established around the drill centre.

y ible ible

r g li g Unlikel N ------9.1 Mino Ne

K-7 Installation of Trenching Residual berms Users of the sea will be notified of the As the flowline, umbilical and power cable will be trenched into the seabed, it

flowlines and backfill could snag presence of new structures via the is unlikely that fishing gear will have the opportunity to become snagged fishing gear y Kingfisher fortnightly bulletins, Notices to during installation. Any berms or spoil piles created during trenching will be ible ible

Mariners and VHF radio broadcast. smoothed off by the plough so snagging hazards left after installation will be r g Unlikel li y

g reduced. N ------9.1 Ver Ne Mino

K-8 Installation of Concrete Could snag The footprint of any protective structures There is the possibility that trawled fishing gear could become snagged on

flowlines mattressing fishing gear y will be minimised the concrete mattressing. However, this will be avoided through minimisation of the footprint of any protective structures present.

r Unlikel y Y Very Unlikely Long Local Low Long Minor 9.1 Ver Low Low Mino

L- Shipping

REPORT REF: GALIA ES D/4127/2011 A-17 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

L-1 Physical Physical Exclusion zone The drilling rig and construction vessels The nearest shipping route is within 2nm of the Galia development. Some presence and presence and could impede will be appropriately lit and sound shipping will be displaced from the immediate vicinity of the development; movement of movement of shipping lanes warnings will be broadcast in poor however there is ample sea room to do so. The 500m safety exclusion zone vessels vessels Increased visibility. around the drilling rig is intended to prevent potential collisions with any collision risk Users of the sea will be notified of the vessels that may be in the area. This will be enforced by a guard vessel. presence and intended movements of construction vessels via the Kingfisher fortnightly bulletins, Notices to Mariners and VHF radio broadcast.

y ible ible

r g A 500m safety exclusion zone will be li g enforced around the drilling rig at all Y Unlikely Moderate Local Low Moderate Minor 9.2 Unlikel Mino Ne times. M - Other marine users

M-1 Physical Physical Localised As per L-1 There is potential for any recreational users to be displaced from the area

presence and presence and displacement of whilst construction is ongoing. However given the distance offshore there is movement of movement of other marine y unlikely to be any significant recreational use.

vessels vessels users ible nificant nificant g The 500m safety exclusion zone around the drilling rig is intended to prevent Unlikel li g y Increased g potential collisions with any vessels that may be in the area. This will be N ------9.3 Ver Ne collision risk Insi enforced by a guard vessel. M-2 Physical Anchoring Anchors could As per L-1 There is no existing oil and gas infrastructure present in the development presence and impact other area and the Alma development is a sufficient distance away that it will not

movement of existing y be impacted. The nearest platform to the development is the Clyde vessels infrastructure platform, located 38km north west of the drill centre. All oil and gas ible ible nificant nificant g infrastructure present in the development area is old and abandoned. As Unlikel li

Increased g y collision risk g stated in the Gardline Geosurvey report (Gardline 2011) all wellheads have N ------9.3 Ver Ne Insi been removed and only seabed depressions remain to mark locations. N- Archaeology

N-1 Physical Anchoring Physical Follow BMAPA protocol for reporting The surveys did not identify any sites of archaeological importance. presence and damage to finds of archaeological significance However, there is potential for undiscovered subsurface archaeological sites movement of undiscovered to be impacted by anchors. As the site has previously been subject to oil

y

vessels archaeology r and gas activity it is assumed the potential for such sites to be present is low. Should a feature be identified, then mitigation measures will be Y Unlikely Short Local Medium Irreversible Minor 9.4 Unlikel Low Low Mino revisited to ensure that the site is not disturbed.

REPORT REF: GALIA ES D/4127/2011 A-18 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Control & Mitigation Measures Residual Impact Assessment Project Aspect Potential Measures Identification of Residual Impact Considering Mitigation Measures Severity Factors Activity Impact

y nificance nificance g Section Section Likelihood Severit Si RIA? (Y/N) Likelihood Duration Spatial Extent Sensitivity Recoverability Significance section Report

N-2 Installation of Physical Physical As per Section N-1 There is the potential for undiscovered subsurface archaeological sites to be flowlines presence of damage to impacted by the installation of flowlines. However, as per Section N-1 the subsea undiscovered potential for such sites to be present is low. Should a feature be identified, infrastructure archaeology then mitigation measures will be revisited to ensure that the site is not

y

and flowlines disturbed.

r Trenching Minor Minor 9.4 Unlikel Y Unlikely Short Local Medium Irreversible and backfill Low Mino

REPORT REF: GALIA ES D/4127/2011 A-19 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

A.3 Production

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

A – Air Quality A-1 Operation and Exhaust gas Localised Ensure all machinery is maintained. The tie-back of the Galia development to the Alma development will maintenance emissions deterioration in Use of cleaner low emission fuels not result in an increase in emissions as a result of power of FPSO air quality generation. The combined Galia and Alma emissions are not Emissions a will be managed via a Increased expected to result in exhaust emissions above those modelled in new Pollution Prevention Control the Alma ES. movement of (PPC) permit that will be applied for export tanker before production commences There will be no additional vessel movements as a result of the tie- and supply in and no rise in emissions from power generation (Section 5.3.3).

vessels y ible ible

r g likel li y

g N ------7.1 Ver Ne Mino A-2 Flaring during Exhaust gas Localised Flare quantities will not exceed Atmospheric emissions from flaring will be moderate (Section initial stages of emissions deterioration in those permitted in the Consent to 5.3.6.1), however pollutants will be dispersed and diluted to levels production air quality Flare. below health and environmental guidelines within 500m of the discharge point. Given the relatively small emissions (compared with multiple large

y combustion sources onshore), the generally dynamic nature ible ible

r g offshore and noting that that development is 280km from sensitive likel li y g receptors these emissions are not expected to have a significant N ------7.1 Ver Ne Mino impact on air quality. B - Climate Change

REPORT REF: GALIA ES D/4127/2011 A-20 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

B-1 Operation and Exhaust gas Loading of Emissions associated with power The tie-back of the Galia development to the Alma development will maintenance emissions greenhouse generation will be managed via an not result in an increase in emissions as a result of power of FPSO from power gases e.g., EU ETS permit generation. The combined Galia and Alma emissions are not Increased generation CO2, CH4, expected to result in exhaust emissions above those modelled in movement of the Alma ES. export tanker There will be no additional vessel movements as a result of the tie-

and supply y in and no rise in emissions from power generation (Section 5.3.3).

vessels See Section 7.2.5 for full discussion. r likel y N ------7.2 Ver Low Low Mino

B-2 Flaring during Exhaust gas Loading of None envisaged Approximately 268,000 tonnes of CO2 will be emitted from gas initial stages of emissions greenhouse flaring over field life (Section 5.5.1). As a comparison the annual

production gases e.g., y emissions represent 0.28% of UK emissions from similar offshore CO2, CH4, activities in 2010 (Section 5.5.1). This is a relatively minor likel y contributor to annual UK emissions and is typical for a standard oil N ------7.2 Ver Low Low Moderate development of this size. C - Water Resource

REPORT REF: GALIA ES D/4127/2011 A-21 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

C-1 Operation and Discharge of Localised Produced water discharge will be The base case is that all produced water from Galia will be re- maintenance produced deterioration in closely monitored to ensure that all injected into the Alma water injection wells with the produced water of FPSO water water quality contaminants are at an acceptable from Alma. level. Oil in water, chemical, Discharge of produced water will therefore only occur during a trip / aromatic and radionuclide outage of the produced water reinjection (PWRI) system onboard concentrations will all be reported the FPSO. A maximum of 95.4 kg of oil could be discharged during via the appropriate OCR and OPPC a 24 hour outage (at 30mgl-1 in 20,000bbls of PW). It is unlikely that permits a trip would last 24 hours). As the Alma and Galia produced fluids OIW concentrations will be within will be co-mingled, the tie-back of Galia will not increase the permitted levels incidence of trips. PW may also be discharged to sea in the event that production (from all wells) starts prior to the commissioning of the injection wells. In the unlikely event that the scenario materialises, It is expected that the maximum quantity of PW discharged (at 30mgl-1) will be 1,521m3day-1 (9564bblday-1) over a period of up to six months (i.e. 182 days). During this period up to 8.3 tonnes of oil may be discharged at a rate of up to 45.6kgday-1. Currents in the project area are of average strength for the CNS (0.2ms-1) and combined with wave action will disperse and dilute chemical discharges during construction. Currents will refresh a 500m radius column of water surrounding the discharge location ible ible

r g within one and a half hours (Section 7.3). Given that discharges are li g expected to be one off events no lasting effect on water quality is

7.3 N ------Possible Possible Ne Mino expected.

REPORT REF: GALIA ES D/4127/2011 A-22 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

C-2 Operation and Discharge of Localised Daily recording of chemical use to Under normal conditions there will be no overboard discharge and maintenance chemicals deterioration in allow more refined and efficient use. as noted above, water quality could only be affected during of FPSO water quality All chemical discharges will be risk occasional outage of the PWRI onboard the FPSO or as a result of assessed and within the DECC production (from all wells) starting prior to the commissioning of the permitted levels as per the relevant injection wells. OCR chemical permit i.e., PON15D. All discharges will be risk assessed and be within permitted levels. Currents in the project area are of average strength for the CNS (0.2ms-1) and combined with wave action will disperse and dilute chemical discharges during construction. Currents will refresh a

r 500m radius column of water surrounding the discharge location within one and a half hours (Section 7.3). No lasting effect on water

7.3 N ------Possible Low Mino quality is expected. D -Seabed conditions D-1 Operation and Discharge of Sediment As per Section C-1 Discharge of produced water will only occur during a trip / outage of maintenance produced contamination the produced water reinjection (PWRI) system onboard the FPSO of FPSO water or as a result of production (from all wells) starting prior to the commissioning of the injection wells. Therefore it is unlikely that there will be any residual impact on sediments.

ible ible

r g li

g N ------7.4 Possible Ne Mino

REPORT REF: GALIA ES D/4127/2011 A-23 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

D-2 Operation and Discharge of Sediment As per Section C-2 Discharge of produced water (and therefore chemicals) will only maintenance chemicals contamination occur during a trip / outage of the produced water reinjection (PWRI) of FPSO system or as a result of production (from all wells) starting prior to the commissioning of the injection wells. All discharges will be risk assessed and be within permitted levels. Currents in the project area are of average strength for the CNS (0.2ms-1) and combined with wave action will disperse and dilute chemical discharges during construction. Currents will refresh a 500m radius column of water surrounding the discharge location within one and a half hours. No lasting effect on water quality is expected. The only chemical likely to be discharged at the seabed is the water-based subsea hydraulic control fluid. Small amounts of control fluid are discharged near the seabed from the directional control valves when they are opened and closed. The typical discharge from one wellhead will be a total of 3m3 per year. No residual impact on sediment is expected.

r N ------7.4 Possible Low Mino E – Plankton E-1 Operation and Discharge of Potential toxic As per Section C-1 Discharge of produced water will only occur during a trip / outage of maintenance produced effect the produced water reinjection (PWRI) system onboard the FPSO of FPSO water or as a result of production (from all wells) starting prior to the ible ible commissioning of the injection wells. r g li g Therefore it is unlikely that there will be any residual impact to N ------8.1 Possible Ne Mino planktonic communities. E-2 Operation and Discharge of Potential toxic As per Section C-2 Discharge of produced water (and therefore chemicals) will only maintenance chemicals effect occur during a trip / outage of the produced water reinjection (PWRI) of FPSO system onboard the FPSO or as a result of production (from all ible ible wells) starting prior to the commissioning of the injection wells. r g li g Therefore it is unlikely that there will be any residual impact to N ------8.1 Possible Possible Ne Mino planktonic communities.

REPORT REF: GALIA ES D/4127/2011 A-24 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

E-3 Operation and Discharge of Organic As per Section C-3 There will be no increase in the cumulative discharge volumes as a maintenance sewage, grey enrichment result of the tie-back of Galia. Therefore it is unlikely that any of FPSO water, food leading to discharges will lead to any measurable organic enrichment. waste and raised biological

drainage oxygen y ible ible nificant nificant water demand. May g likel li g y change balance g Ver N ------8.1 Ne of food chain. Insi F - Benthic communities F-1 Operation and Discharge of Potential toxic As per Section C-1 Discharge of produced water will only occur during a trip / outage of maintenance produced effect the produced water reinjection (PWRI) system onboard the FPSO of FPSO water or as a result of production (from all wells) starting prior to the commissioning of the injection wells. ible ible Therefore it is unlikely that there will be any residual impact to r g li

g benthic communities. N ------8.2 Possible Possible Ne Mino F-2 Operation and Discharge of Potential toxic As per Section C-2 Discharge of produced water (and chemicals) will only occur during maintenance chemicals effect a trip / outage of the produced water reinjection (PWRI) system of FPSO onboard the FPSO or as a result of production (from all wells) starting prior to the commissioning of the injection wells. The only chemical likely to be discharged at the seabed is the water-based subsea hydraulic control fluid. Small amounts of control fluid are discharged near the seabed from the directional control valves when they are opened and closed. The typical 3 ible ible discharge from one wellhead will be a total of 3m per year. No toxic r g li

g impact on benthic communities is expected. N ------8.2 Possible Ne Mino G - Fish and shellfish

REPORT REF: GALIA ES D/4127/2011 A-25 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

G-1 Operation and Discharge of Potential toxic As per Section C-1 Discharge of produced water will only occur during a trip / outage of ible ible

maintenance produced effect the produced water reinjection (PWRI) system onboard the FPSO. r g li of FPSO water g Therefore it is unlikely that there will be any residual impact on fish Possible Ne N ------8.3 Mino and shellfish. G-2 Operation and Discharge of Potential toxic As per Section C-2 Discharge of produced water (and chemicals) will only occur during maintenance chemicals effect a trip / outage of the produced water reinjection (PWRI) system of FPSO onboard the FPSO or as a result of production (from all wells) starting prior to the commissioning of the injection wells. The only chemical likely to be discharged at the seabed is the water-based subsea hydraulic control fluid. Small amounts of control fluid are discharged near the seabed from the directional control valves when they are opened and closed. The typical discharge from one wellhead will be a total of 3m3 per year. ible ible

r g Conditions in the vicinity of the development are such that any li g discharge will be quickly dispersed and therefore exposure of fish N ------8.3 Possible Possible Ne Mino and shellfish to these chemicals will be reduced. H – Seabirds

H-1 Operation and Discharge of Potential toxic As per Section C-1 Discharge of produced water will only occur during a trip / outage of maintenance produced effect the produced water reinjection (PWRI) system onboard the FPSO of FPSO water or as a result of production (from all wells) starting prior to the

ible ible commissioning of the injection wells. nificant nificant g li g g Therefore there will be no residual impact on the seabird N ------8.4 Possible Possible Ne Insi community. H-2 Operation and Discharge of Potential toxic As per Section C-2 Discharge of produced water will only occur during a trip / outage of maintenance chemicals effect the produced water reinjection (PWRI) system onboard the FPSO of FPSO or as a result of production (from all wells) starting prior to the

ible ible commissioning of the injection wells. nificant nificant g li g g Therefore there will be no residual impact on the seabird N ------8.4 Possible Ne Insi community.

REPORT REF: GALIA ES D/4127/2011 A-26 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

H-2 Increased Increased Localised No mitigation envisaged There will be no additional vessels visiting the development as a movement of vessel activity disturbance of result of the tie-back of the Galia development. Therefore this is not export tanker in region seabirds from considered to be a significant threat to seabirds due to the existing and supply the sea surface level of shipping activity in the area. vessels

y

ible ible nificant nificant g Unlikel li g y

g N ------8.4 Ver Ne Insi I - Marine mammals

I-1 Operation and Discharge of Potential toxic As per Section C-1 Discharge of produced water will only occur during a trip / outage of maintenance produced effect y the produced water reinjection (PWRI) system onboard the FPSO

of FPSO water ible or as a result of production (from all wells) starting prior to the nificant nificant g Unlikel li g y

g commissioning of the injection wells. N ------8.5 Ver Ne Insi Therefore there will be no residual impact on marine mammals.

I-2 Operation and Discharge of Potential toxic As per Section C-2 Discharge of produced water will only occur during a trip / outage of maintenance chemicals effect y the produced water reinjection (PWRI) system onboard the FPSO

of FPSO ible or as a result of production (from all wells) starting prior to the g Unlikel li y

g commissioning of the injection wells. N ------8.5 Ver Ne Insentient Therefore there is no significant threat to marine mammals. J - Marine protected sites and species

REPORT REF: GALIA ES D/4127/2011 A-27 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

J-1 Operation and Discharge of Potential toxic As per Section C-1 Eight species of cetacean are known to frequent the project area at maintenance produced effects through certain times of the year. All cetaceans are EPS. The impact on of FPSO water bioaccumulatio marine mammals was assessed in I-2 n of chemicals and hydrocarbons in food chain Smothering

y ible ible nificant nificant g li g

g N ------8.6 Unlikel Insi Ne J-2 Operation and Discharge of Potential toxic As per Section C-2 Eight species of cetacean are known to frequent the project area at maintenance chemicals effects through certain times of the year. All cetaceans are EPS. The impact on of FPSO bioaccumulatio marine mammals was assessed in I-3 n of chemicals and hydrocarbons in food chain

y ible ible nificant nificant g li g

g N ------8.6 Unlikel Insi Ne J-3 Increased Subsea noise Can cause No measures envisaged Eight species of cetacean are known to frequent the project area at movement of physical injury certain times of the year. All cetaceans are EPS. The impact on export tanker or disturbance marine mammals was assessed in I-4. and supply to protected

vessels species y

ible ible

r g Unlikel li y

g N ------8.6 Ver Ne Mino K - Commercial fisheries

REPORT REF: GALIA ES D/4127/2011 A-28 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

K-1 Presence of Safety Exclusion from Users of the sea will be notified of There will be a new 500m safety exclusion zone around the Galia the Galia drill exclusion fishing grounds the presence of the new safety drill centre which will result in fishing vessels being displaced from centre zones exclusion zone (around Galia) via their fishing grounds. This will be enforced by a guard vessel. The the Kingfisher fortnightly bulletins, exclusion area (0.8km2) is small in comparison to the wider ICES Notices to Mariners and VHF radio Block (3,086km2). broadcast. However the Galia development area is not considered to be a commercially important ground for pelagic and demersal species. An average of 125.4 tonnes of fish and shellfish, worth approximately £115,703 are landed each year from the ICES rectangle (41F2) that covers the Galia development area.

y ible ible

r g Likel li y g Y Very Likely Moderate Local Low Moderate Minor 9.1 Ver Ne Mino

K-2 Increased Increased Potential All vessels will comply with The tie-back of the Galia development to the Alma development will movement of vessel activity collision risk international navigation regulations not result in any increase in vessel activity in the region. Therefore export tanker in region and codes. the standard laws of the sea are sufficient to mitigate any risks. and supply vessels

y

r Unlikel y N ------9.1 Ver Low Low Mino

K-3 Presence of Physical Could snag Users of the sea will be notified of There is the possibility that trawled fishing gear could become subsea presence of fishing gear the presence of new structures via snagged on subsea infrastructure. The majority of the structures will infrastructure subsea the Kingfisher fortnightly bulletins, be within a 500m radius safety exclusion zone. The mitigation ible ible infrastructure and updates to Admiralty Charts. measures are thought to be sufficient to negate any residual r g li and flowlines g All subsea structures have been impacts. N ------9.1 Possible Possible Ne Mino designed to be fishing friendly

REPORT REF: GALIA ES D/4127/2011 A-29 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

L – Shipping

L-1 Increased Increased Increased All vessels will comply with The nearest shipping lane is within 2nm of the Galia development.

movement of vessel activity collision risk y international navigation regulations There will be no increase in vessel activity as a result of the Galia export tanker in region and codes. tie-back. ible ible nificant nificant g Unlikel li g and supply y g Ver N ------9.2 Ne vessels Insi

M - Other marine users

M-1 Increased Increased Increased All vessels will comply with There is the potential for any recreational users to be displaced from movement of vessel activity collision risk international navigation regulations the area for the life of the development (10 years). However given export tanker in region and codes. the historical use of the area for oil and gas, there is little and supply recreational use of the area (Section 9.3). In addition, the tie-back of vessels the Galia development will not result in any increase in vessel activity at the development. There is no existing oil and gas infrastructure present in the

development area. The nearest platform to the development is the y Clyde platform, located 38km north west of the northern drill centre.

r The 500m safety exclusion zone around the development is Unlikel y intended to prevent potential collisions with any vessels that may be N ------9.3 Ver Low Low Mino in the area. This will be enforced by the guard vessel.

REPORT REF: GALIA ES D/4127/2011 A-30 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

A.4 Accidental Events

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

A - Water Resource A-1 Chemical / Diesel, crude Localised Accidental spills will be kept to a A large number of chemicals will be used during construction hydrocarbon or chemical deterioration in minimum through training, good activities, particularly associated with well engineering. All chemicals release (< 1 spill water quality housekeeping and through will be risk assessed and permitted in the appropriate manner. tonne) (including storage/handling procedures e.g., Although spilt chemicals/diesel may have an acute toxic effect on OBMs) sumps, drains and bunding should immediate discharge they will be quickly diluted and dispersed in catch accidental spills. the water column. Currents within the project area will refresh a Management controls will be in column of water within 500m of the discharge point within one and a place to eliminate bunkering spills half hours, although it may take slightly longer for the water column e.g. only bunkering during day light to return to pre-impact levels if the chemical release is of sufficient and in good weather. quantity. Location specific OPEPs will be in OBM chemical spills may take longer to disperse as the heavier oil place for drilling and production. has less of a tendency to evaporate. However a small spill is still

r The OPEPs will detail all emergency likely to break up with a couple of days. procedures that will be in place to

7.3 N ------Possible Possible Low Mino minimise any spill. A-2 Chemical / Diesel, crude Localised As per Section A-1 but in addition: A spill of <10 tonnes is more likely to occur during construction hydrocarbon or chemical deterioration in EnQuest has access to Tier 1, 2 activities, e.g., during bunkering. Diesel is a Group 2 oil which release (1-10 spill water quality and 3 oil spill response capabilities evaporates quickly on release. Typically 90% of a large diesel spill tonnes) (including through Oil Spill Response (OSR). evaporates or disperses naturally within the water column within OBMs) one to two days (ITOPF 2007). For a spill of <10 tonnes it is possible that it will have dispersed within a few hours. Crude oil or OBM chemical spills may take longer to disperse as the

y

r heavier oil has less of a tendency to evaporate. Mitigation measures in place should be sufficient to minimise the risk of a spill

7.3 N ------Unlikel Low Low Mino and any deterioration in water quality is likely to be transient.

REPORT REF: GALIA ES D/4127/2011 A-31 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

A-3 Chemical / Diesel, crude Deterioration in As for A-2 but in addition: Four scenarios have been identified which could result in a spill of hydrocarbon or chemical water quality EnQuest is a member of OSPRAG crude oil or diesel >10 tonnes: loss of containment from the drilling release (>10 spill which will provide support in a well rig, loss of well control, total loss of inventory from the FPSO and tonnes) (including blow out event. total loss of inventory from the export tanker (see Section 6.3). OBMs) Control measures will be in place to A diesel spill will very quickly evaporate and disperse in the marine ensure rapid response to loss of environment. Oil spill modelling indicates the diesel inventory from pipeline containment. These will be the export tanker (the largest inventory) would naturally disperse or outlined in the OPEP. evaporate within 10 hours (see Section 6.3.2). Crude oil takes longer to disperse and an intervention response may be necessary to help break it up before it beaches on the shoreline. Water quality is likely to deteriorate in the immediate vicinity of the spill as hydrocarbons are dispersed through the water column.

y y However, it will be naturally biodegraded by microbes within one to two months (NOAA 2006). The concentration and likelihood of

r r natural biodegradation will obviously be dependent on the scale of Unlikel y

the incident. However, generally the deterioration in water quality 7.3 Y Mino Ver Very Unlikel Short Short Extensive Moderate Moderate Low Low Mino will be short –term. B -Seabed conditions B-1 Overboard Dropped Scour around Every reasonable measure will be Scour is likely around any object remaining on the seabed. loss of objects objects taken to retrieve dropped objects. However, given the mitigation measures in place any residual equipment or If the object cannot be retrieved a impacts are likely to be negligible. waste PON2 will be submitted to the DECC. A dropped objects plan will be ible ible

r g developed to address risk of li g dropping objects during construction

7.4 N ------Possible Ne Mino and operations. B-2 Chemical / Diesel, crude Sediment As per Section A-1 A large number of chemicals will be used during construction hydrocarbon or chemical contamination activities, particularly associated with drilling the wells. All chemicals release (< 1 spill will be risk assessed and permitted in the appropriate manner.

tonne) (including

r A spill <1 tonne is likely to be at the sea surface from the drilling rig OBMs) or support vessel, and would disperse within a couple of hours.

N ------Possible Possible Low Mino Therefore, it is unlikely that hydrocarbons will reach the seabed. 7.4

REPORT REF: GALIA ES D/4127/2011 A-32 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

B-3 Chemical / Diesel, crude Sediment As per Section A-2 The majority of spills are likely to be at the sea surface or in the hydrocarbon or chemical contamination water column. The likelihood of a spill between 1 and 10 tonnes release (1-10 spill occurring during construction is 0.5% for the Galia development. tonnes) (including The probability of an incident involving the subsea system is

y y

OBMs) r approximately 3% over field life (Section 6.2.2). A spill of crude oil r

from the production flowline could contaminate sediments and 7.4 Mino Unlikel Y Unlikel Low Low Mino persist for some time however the extent will be localised. Short Local High Moderate

REPORT REF: GALIA ES D/4127/2011 A-33 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

B-4 Chemical / Diesel, crude Sediment As per Section A-3 During construction, two scenarios have been identified which could hydrocarbon or chemical contamination result in a spill of crude oil or diesel >10 tonnes: loss of containment release (>10 spill from the drilling rig and total loss of well control (see Section 6.3). tonnes) (including Modelling of a 15 day crude oil loss of 35,775m3 (29,880 tonnes) OBMs) from a loss of well control shows there is a 1% chance of oil beaching along the coastline of one or more of the countries bordering the North Sea. Trajectory modelling, presented in Section 7.3 and Appendix B, indicates that with a prevailing wind towards the UK coastline it will take approximately 200 hours for the spill to beach on the North Yorkshire coastline. With a prevailing wind towards the nearest international boundary a crude oil spill would first cross the cross the UK / Norway median line (within 9 hours) and then the Norway/Denmark median line after 28 hours. Taking into consideration evaporation and dispersion approximately 30,931m3 of crude oil could beach along the Danish coast within 136 hours of the spill occurring. Any components that settle to the seabed will be naturally biodegraded by microbes within one to two months. Elevated concentrations of hydrocarbons may be noticeable in sediments close to the discharge point after a large spill. Given the previous use of the area for oil and gas development, levels of hydrocarbon contamination are not expected to rise over existing historical levels. Crude oil that beaches has the potential to contaminate beach sediments. However, as a spill of this magnitude is extremely rare it is highly unlikely that there will be a residual impact during this development.

y

r r Unlikel y

7.4 Ver Y Very Unlikely Moderate Extensive High Moderate Mino Medium Medium Mino

REPORT REF: GALIA ES D/4127/2011 A-34 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

C - Plankton C-1 Chemical / Diesel, crude Potential toxic As per Section A-1 Accidental spills of chemicals will be rapidly diluted and dispersed in hydrocarbon or chemical effects the marine environment. It is expected that spilt materials will not be release (< 1 spill in the water column for long enough or at concentrations that are tonne) (including likely to pose a significant toxic effect to plankton. Although

OBMs) r vulnerable to a change in water quality the plankton community undergoes a continual change in individuals with the surrounding

8.1 Possible Low Mino waters and therefore is not considered sensitive. N ------C-2 Chemical / Diesel, crude Potential toxic As per Section A-2. A hydrocarbon spill of <10 tonnes will be diluted and dispersed in hydrocarbon or chemical effect the water column within hours to at most one or two days. release (1-10 spill Concentrations of hydrocarbons may reach levels that pose a tonnes) (including significant toxic effect to plankton, but this is likely to be transient, OBMs) returning to background concentrations within a few tidal cycles.

y

r Although vulnerable to a change in water quality the plankton community undergoes a continual change in individuals with the

8.1 N ------Unlikel Low Low Mino surrounding waters and therefore is not considered sensitive. C-3 Chemical / Diesel, crude Potential toxic As per Section A-3 Concentrations of hydrocarbons may reach levels that pose a hydrocarbon or chemical effects significant toxic effect to plankton. Although vulnerable to a change release (>10 spill in water quality the plankton community undergoes a continual

y tonnes) (including y change in individuals with the surrounding waters and therefore is OBMs) generally not considered sensitive. However, a major crude oil spill

r r does have the potential to affect a large area of water and therefore Unlikel y

there may be more extensive damage to plankton communities. 8.1 Y Mino Ver Very Unlikel Short Short Extensive High Short Low Low Mino The likelihood of this happening is extremely rare. D - Benthic communities D-1 Overboard Dropped Physical As per Section B-1 Sessile species within the immediate impact footprint of the dropped loss of objects damage to object are likely to be killed and species within the immediate vicinity equipment or individuals may be smothered by the repositioning of sediment. The benthic ible ible

r waste g community is typical of the CNS and no rare or protected species li g were identified in the site survey. Any impacts will be restricted to

8.2 N ------Possible Possible Ne Mino individuals and not felt at a population level.

REPORT REF: GALIA ES D/4127/2011 A-35 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

D-2 Chemical / Diesel, crude Smothering As per Section A-1 Accidental spills of chemicals will be rapidly diluted and dispersed in hydrocarbon or chemical Potential toxic the marine environment. The majority of spills are likely to be at the release (< 1 spill effects sea surface in water depths of approximately 80m (LAT). It is tonne) (including expected that spilt materials will not be in the water column for long OBMs) enough or at concentrations that are likely to pose a significant toxic effect to the benthic community. Any spill at the seabed would come

r from a leak in the 8" production flowline or from the wellhead. A spill of <1 tonne is likely to disperse and any toxic effects on benthic

8.2 - - - - Possible Low Mino species are expected to be localised. N - - D-3 Chemical / Diesel, crude Smothering As per Section A-2 As per Section B-3. Spills from the surface are unlikely to reach the hydrocarbon or chemical Potential toxic seabed and pose a threat to the benthic community. release (1-10 spill effects Crude oil has the potential to smother benthic communities or tonnes) (including present a toxic risk if it reaches the seabed or is discharged at the OBMs) seabed. Individuals in the immediate vicinity of the spill location may be killed. However, the water column is likely to quickly dilute

y

r and disperse the spill and any toxic effects such that outside the immediate vicinity there are unlikely to be any residual impacts. The

8.2 N ------Unlikel Low Low Mino community as a whole is not expected to be affected. D-4 Chemical / Diesel, crude Smothering As per Section A-3 During construction, two scenarios have been identified which could hydrocarbon or chemical Potential toxic result in a spill of crude oil or diesel >10 tonnes: loss of containment release (>10 spill effects from the drilling rig and total loss of well control (see Section 6.3). tonnes) (including It is highly unlikely that oil will pool on the seabed so in most OBMs) scenarios there is little direct risk to benthic communities of smothering. Elevated concentrations of hydrocarbons may be noticeable in sediments if the spill reaches the seabed which may affect community structure on a local scale. However, any change is unlikely to be sufficient to change the classification of sediments from unpolluted, and toxic effects on the benthic community are expected to be limited.

y y There is the possibility that if oil was to beach, those benthic communities in shallow waters would be smothered by emulsified

r oil. However, given the fact that a spill of the magnitude necessary Unlikel y

for oil to beach is highly unlikely, the EIA concluded that the Y Minor 8.2 Ver Very Unlikel Short Short Extensive High Moderate Medium Medium Mino significance of an impact on benthic communities is minor. E - Fish and shellfish

REPORT REF: GALIA ES D/4127/2011 A-36 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

E-1 Overboard Dropped Physical As per Section B-1 Sessile species within the immediate impact footprint of the loss of objects damage to dropped object are likely to be killed and species within the ible ible

r equipment or individuals g immediate vicinity may be smothered by the repositioning of li waste g sediment. Any impacts will be restricted to individuals and not felt

8.3 - - - - Possible Ne N - - Mino at a population level. E-2 Chemical / Diesel, crude Potential toxic As per Section A-1 Discharged materials will not be present within the water column for hydrocarbon or chemical effects long enough or at concentrations that are likely to pose a significant

release (< 1 spill r toxic threat to fish communities as a whole. Concentrations outside tonne) (including the immediate discharge area/time will be close to background or

8.3 N ------OBMs) Possible Low Mino undetectable. E-3 Chemical / Diesel, crude Potential toxic As per Section A-2 Acute toxic effects to fish and shellfish species will be restricted to hydrocarbon or chemical effects the immediate area of the spill and for the duration of the spill release (1-10 spill release. However, high levels of toxic effects on fish spawning may tonnes) (including have longer term implications to stock levels. These long-term OBMs) chronic effects include reduced fecundity and breeding failure. However, it is likely that discharged materials will not be present within the water column for long enough or at concentrations that

y

r are likely to pose a significant toxic threat to marine ecology as a whole. Concentrations outside the immediate discharge area/time

8.3 N ------Unlikel Low Low Mino will be close to background or undetectable.

REPORT REF: GALIA ES D/4127/2011 A-37 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

E-4 Chemical / Diesel, crude Potential toxic As per Section A-3 In fish life cycles the egg and juvenile stages are the most hydrocarbon or chemical effects vulnerable to toxicity in the water column, as adult fish are highly release (>10 spill mobile and generally able to avoid polluted areas. Localised tonnes) (including fatalities would occur in the immediate vicinity of the spill, but fish OBMs) are likely to avoid the area if the situation persists, and any effects are unlikely to be felt on a population level. As discussed in Section 8.3.2 the Galia development area lies within the spawning and nursery areas for mackerel, lemon sole, sprat, haddock and whiting (Coull et al. 1998). A major spill during a particular sensitive period could affect recruitment for that year. However, the spawning/nursery grounds span large areas of the North Sea which will mean that long-term changes to populations are minor. In general, lighter refined petroleum products such as diesel and gasoline are more likely to mix in the water column and are therefore more toxic to marine life. However, they tend to evaporate quickly (as demonstrated in Section 6.3) and do not

y y persist long in the environment. Although heavier residual oils tend to have specific gravities greater than sea water, causing them to

r r sink once spilled, the reservoir oil is light crude which is unlikely to Unlikel y sink. A major hydrocarbon spill has therefore been assessed as 8.3 Y Very Unlikel Mino Ver Moderate Moderate Extensive Medium Moderate Medium Medium Mino having the potential for an impact of minor significance on fish. F – Seabirds F-1 Overboard Discharge of Potential toxic As per Section B-1 It is possible that seabirds could ingest large items of refuse which

y

loss of waste items effect r typically causes the death of the affected birds. However the equipment or such as mitigation in place is sufficient to negate any residual impacts. N ------8.4 Unlikel waste plastic bags Low Mino

REPORT REF: GALIA ES D/4127/2011 A-38 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

F-2 Chemical / Diesel, crude Potential toxic As per Section A-1 Accidental spills of chemicals will be rapidly diluted and dispersed hydrocarbon or chemical effects with the marine environment. Uptake of toxic chemicals by plankton release (< 1 spill can have effects throughout the food chain, either as a result of tonne) (including direct mortality of food species or through transmission of OBMs) bioaccumulating chemicals to higher trophic levels. Discharged materials will not be present within the water column for long enough or at concentrations that are likely to pose a significant toxic threat to marine ecology as a whole. Concentrations outside the immediate discharge area/time will be close to background or undetectable. Hydrocarbon releases have the potential to smother seabirds. Oil spill effects include mortality by ingesting oil from feathers during

r preening, as well as by hypothermia from matted feathers. However, spills < 1 tonne generally disperse within a few hours and N ------8.4 Possible Low Mino are unlikely to present a risk to seabirds F-3 Chemical / Diesel, crude Smothering As per Section A-2 The likelihood of a spill between 1 and 10 tonnes occurring during hydrocarbon or chemical Potential toxic construction is 0.5% for the single Galia well. The spill is likely to be release (1-10 spill effects at the sea surface and would disperse within a couple of hours to a tonnes) (including few days depending on the type of hydrocarbon spilt.

OBMs) Hydrocarbon releases have the potential to smother seabirds. Oil spill effects include mortality by ingesting oil from feathers during preening, as well as by hypothermia from matted feathers. However, overboard spills between 1 and 10 tonnes generally

y

r disperse within a few days depending on the type of hydrocarbon spilt. The mitigation measures, when implemented, should be N ------8.4 Unlikel Low Low Mino sufficient to prevent smothering of more than a few individuals.

REPORT REF: GALIA ES D/4127/2011 A-39 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

F-3 Chemical / Diesel, crude Smothering As per Section A-3 During construction, two scenarios have been identified which could hydrocarbon or chemical Potential toxic result in a spill of crude oil or diesel >10 tonnes: loss of containment release (>10 spill effects from the drilling rig and total loss of well control (see Section 6.3). tonnes) (including 3 Modelling shows that in the event of a crude oil loss of 35,775m OBMs) (29,880 tonnes) from a 15 day loss of well control then there is a 1% chance of oil beaching along the coastline of one or more of the countries bordering the North Sea. Trajectory modelling, presented in Section 6.3 and Appendix B, indicates that with a prevailing wind towards the UK coastline it will take approximately 200 hours for the spill to beach on the North Yorkshire coastline. With a prevailing wind towards the nearest international boundary a crude oil spill would first cross the cross the UK / Norway median line (within 9 hours) and then the Norway/Denmark median line after 28 hours. Taking into consideration evaporation and dispersion approximately 30,931m3 of crude oil could beach along the Danish coast within 136 hours of the spill occurring. Any spill of the magnitude modelled above is likely to significantly impact populations of seabirds. Seabirds that spend the majority of their time on the sea surface are most vulnerable as birds can be smothered by oil, or their feathers can become contaminated with hydrocarbons, which in turn may be ingested. Seabird vulnerability to hydrocarbon pollution is generally low for most of the year, with a significant increase in vulnerability in January and October. Should a spill occur during one of these sensitive periods an intervention response may be required to minimise the risk of smothering and species injury. It is highly unlikely that a spill of the magnitude

y y discussed above will occur. Mitigation measures outlined in the OPEP and management controls to eliminate spills should prevent any sizeable spills. Given the likelihood of an impact occurring is Unlikel y h g

unlikely the EIA concluded that significance of the impact is Y Moderate 8.4 Ver Very Unlikel Long Long Extensive Very High Long Hi Moderate Moderate moderate. G - Marine mammals G-1 Overboard Discharge of Potential toxic As per Section B-1 It is possible that marine mammals could ingest large items of

y

loss of waste items effect r refuse which typically causes the death of the affected animal. equipment or such as However the mitigation in place is sufficient to negate any residual Unlikel N ------8.5 waste plastic bags Low Mino impacts.

REPORT REF: GALIA ES D/4127/2011 A-40 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

G-2 Chemical / Diesel, crude Potential toxic As per Section A-1 Accidental spills will be diluted and dispersed within the marine hydrocarbon or chemical effect environment. Spilt materials will not be present within the water release (< 1 spill column for long enough or at concentrations that are likely to pose a

tonne) (including r significant toxic threat to marine mammals. Concentrations outside OBMs) the immediate discharge area/time will be close to background or Possible Low Mino undetectable. N ------8.5 G-3 Chemical / Diesel, crude Potential toxic As per Section A-2 The likelihood of a spill between 1 and 10 tonnes occurring during hydrocarbon or chemical effect construction is 0.5% for the development. The spill is likely to be at release (1-10 spill the sea surface and would disperse within a couple of hours to a tonnes) (including few days depending on the type of hydrocarbon spilt. OBMs) Discharged materials will not be present within the water column for long enough or at concentrations that are likely to pose a significant

y

toxic threat to marine ecology as a whole. r In addition, a spill of this size could be easily avoided by these N ------8.5 Unlikel Low Low Mino mobile animals.

REPORT REF: GALIA ES D/4127/2011 A-41 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

G-4 Chemical / Diesel, crude Potential toxic As per Section A-3 There is potential for marine mammals to be significantly affected if hydrocarbon or chemical effect a large crude oil spill was to occur. Although the region surrounding release (>10 spill the Galia development is not considered to be particularly important tonnes) (including for marine mammals, pods and individuals have been observed OBMs) throughout the year. Should a major release of crude oil occur, there is the potential that individuals could be affected. In addition should any oil reach the shoreline, haul out sites for pinnipeds may be impacted. Pinnipeds are particularly sensitive between October and January when they are on land pupping and again between February and March during their annual moult. Neonatal pups are particularly at risk from oil coming ashore. Cetaceans have smooth hairless skins over a thick layer of insulating blubber, so oil is unlikely to adhere persistently or cause a breakdown in insulation. Marine mammals must surface to breathe and they may inhale vapours given off the spilt oil and their eyes may be vulnerable to major pollution. Indirect effects may also be caused through contamination and depletion of food resources. Due to the transient nature of cetaceans, it is likely that individuals not in the immediate area of the spill when it occurs will avoid the area and it is possible that the number of individuals affected could be small. However, if a substantial number of a population where affected there could be knock on effects to breeding and the long- term viability of the population. Recovery rates of land based marine mammals such as seals could be longer particularly if a spill affected a breeding season. All cetaceans are protected under the EC Habitats Directive as EPS and are classed as ecologically important. Although a major oil spill could have a significant impact on marine mammals the EIA concluded that the significance of the impact was minor based on the fact that a spill of this magnitude is extremely unlikely to occur.

y y

r r Unlikel y

8.5 Y Mino Ver Very Unlikel Moderate Moderate Extensive Very High Moderate Medium Medium Mino

REPORT REF: GALIA ES D/4127/2011 A-42 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

H - Marine protected sites and species H-2 Chemical / Diesel, crude Smothering of As per Section A-1 There are no protected sites within 40km of the Galia development hydrocarbon or chemical protected area and a spill of <1 tonne is unlikely to travel far before being release (< 1 spill species dispersed.

tonne) (including

Potential effects r Marine mammals are a European Protected Species and are likely OBMs) on integrity of a to be present in the vicinity of the project area. The impact of an protected site Possible Low Mino accidental spill on marine mammals was assessed in G-2 N ------8.6 H-3 Chemical / Diesel, crude Smothering of As per Section A-2 There are no protected sites within 40km of the Galia development hydrocarbon or chemical protected area and a spill of <10 tonnes is unlikely to travel far before being release (1-10 spill species dispersed. tonnes) (including Potential effects Marine mammals are a European Protected Species and are likely OBMs) on integrity of a to be present in the vicinity of the project area. The impact of a

y

protected site r release of hydrocarbons (< 10 tonnes) on marine mammals was assessed in G-2. N ------8.6 Unlikel Low Low Mino

H-4 Chemical / Diesel, crude Smothering of As per Section A-3 There is potential for protected sites and species to be significantly hydrocarbon or chemical protected affected if a large crude oil spill was to occur. The impact on release (>10 spill species protected species of marine mammals and seabirds are discussed tonnes) (including Potential effects in Sections F-3 and G-4 above. OBMs) on integrity of a Although there are no designated protected sites within 40km of the protected site Galia field, modelling shows that in the event of a total loss of well control, there is potential for impacts over a widespread area and the possibility of crude oil beaching on the coastline. There are numerous protected areas along the coastline of the North Sea that could potentially be affected. Should a spill with potential to affect a protected area occur, an intervention response would be required. It is highly unlikely that a spill of the magnitude discussed above will occur. Mitigation measures outlined in the OPEP and management controls to

eliminate spills should prevent any sizeable spills. As the likelihood y of such a spill occurring is extremely rare the EIA concluded that significance of the impact is minor. Unlikel y

Y Minor 8.6 Ver Very Unlikely Very Unlikely Moderate Extensive Very High Moderate Medium Medium Moderate

REPORT REF: GALIA ES D/4127/2011 A-43 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

I - Commercial fisheries I-1 Overboard Dropped Could snag As per Section B-1 The mitigation measures in place are considered sufficient to ible ible

r loss of objects fishing gear g reduce the impact on commercial fishing. li equipment or g Possible Ne N ------9.1 waste Mino I-2 Chemical / Diesel, crude Potential As per Section A-1 Accidental spills of chemicals will be rapidly diluted and dispersed hydrocarbon or chemical decrease in with the marine environment. Spilt materials will not be present release (< 1 spill catch if stocks within the water column for long enough or at concentrations that tonne) (including affected are likely to pose a significant toxic threat to marine ecology as a

OBMs) r whole. Concentrations outside the immediate discharge area/time will be close to background or undetectable. Therefore there is N ------9.1 Possible Low Mino unlikely to be a knock-on effect on commercial fisheries. I-3 Chemical / Diesel, crude Potential As per Section A-2 Acute toxic effects to fish and shellfish species will be restricted to hydrocarbon or chemical decrease in the immediate area of the spill and for the duration of the spill release (1-10 spill catch if stocks release. However, high levels of toxic effects on fish spawning may tonnes) (including affected have longer term implications to stock levels. These long-term OBMs) chronic effects include reduced fecundity and breeding failure which will have a knock-on effect on commercial fisheries in the area. However, it is likely that spilt materials will not be present within the water column for long enough or at concentrations that are likely to

y

r pose a significant toxic threat to marine ecology as a whole. Concentrations outside the immediate discharge area/time will be N ------9.1 Unlikel Low Low Mino close to background or undetectable.

REPORT REF: GALIA ES D/4127/2011 A-44 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

I-4 Chemical / Diesel, crude Potential As per Section A-3 Modelling shows that in the event of a total loss of well control, there hydrocarbon or chemical decrease in is the potential for an extensive area of the North Sea to be affected. release (>10 spill catch if stocks However an incident of this magnitude is unlikely. tonnes) (including affected A major crude oil spill has the potential to damage fishing vessels OBMs) Damage to passing through the project location at the time of the event and has boats and gear the potential to cause a decrease in catch if fish stocks are affected. It is expected that if boats are present in the area at the time of a spill they will be able to avoid the slick so it is considered highly unlikely gear or boats will be damaged. However, vessels may be excluded from the affected area during the clean-up operations. Generally, for short periods of time the fishing industry can relocate to other grounds without any detrimental impacts to catch, but a spill that affects large areas of sea may make it harder to relocate. It fish stocks are contaminated they make take a number of years to recover and fishing grounds could be closed with substantial loss of income for industry. Experience from major spills has shown that the long-term effects on wild fish stocks are unlikely because the normal over-production of eggs provides a reservoir to compensate for any localised losses. However, there could be a loss of market confidence as people may be unwilling to buy fish caught in a

contaminated area. y Although the potential impacts could be of major significance to the

r fishing industry the fact that a spill of the magnitudes discussed Unlikel y

above is highly unlikely has meant that the EIA concluded the Y Minor 9.1 Ver Very Unlikely Very Unlikely Moderate Extensive Medium Moderate Medium Medium Mino residual impact is of minor significance. J- Shipping J-1 Overboard Dropped Could cause As per Section B-1. The mitigation measures in place are considered sufficient to

loss of objects hazard to reduce the impact on shipping. r equipment or shipping N ------9.2 waste Possible Low Mino

REPORT REF: GALIA ES D/4127/2011 A-45 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Determination of Potential Impact EIA Consideration of Mitigation Measures Residual Impact Assessment Project Aspect Potential Mitigation Measures Identification of Residual Impact Considering Severity Factors Activity Impact Mitigation Measures

y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

J-2 Chemical / Diesel, crude Damage to As per Section A-3 Modelling shows that in the event of a total loss of well control there hydrocarbon or chemical vessels is the potential for an extensive area of the North Sea to be affected. release (>10 spill Restrictions on However, an incident of this magnitude is unlikely. tonnes) (including shipping lanes If the spill is extensive then shipping routes in the region could be OBMs) closed to allow the oil spill response to be undertaken. It is possible that shipping could be routed around the affected area but there might be financial implications associated with longer routes and delays. As the event is very unlikely to occur the residual impact

y has been assessed as being insignificant.

r Unlikel y N ------9.2 Ver Low Low Mino

K - Other marine users K-1 Overboard Dropped Could cause As per Section B-1 The mitigation measures in place are considered sufficient to loss of objects hazard to reduce the impact on other marine users. equipment or shipping waste ible ible

r g li g N ------9.3 Possible Possible Ne Mino

K-4 Chemical / Diesel, crude Damage to As per Section A-3 Modelling shows that in the event of a total loss of well control there hydrocarbon or chemical vessels is potential for an extensive area of the North Sea to be affected. release (>10 spill Restricted However, an incident of this magnitude is unlikely. tonnes) (including access If crude oil reaches the coastline, nearshore activities could be OBMs) affected if restrictions are imposed to assist with the response operation. There may also be knock-on effects on the tourist industry if the spill beaches in substantial quantities. As the event is very unlikely to occur the residual impact has been assessed as being insignificant

y

r Unlikel y N ------9.3 Ver Low Low Mino

REPORT REF: GALIA ES D/4127/2011 A-46 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

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y nificance nificance g Likelihood Severit Si (Y/N) RIA? Likelihood Duration Spatial Extent Sensitivity Recoverability Significance Report section Section Section

L - Archaeology L-1 Overboard Dropped Physical Follow BMAPA protocol for The surveys did not identify any sites of archaeological importance. loss of objects damage to reporting finds of archaeological However, there is the potential for undiscovered subsurface

equipment or undiscovered y significance archaeological sites to be impacted by dropped objects. As the site waste archaeology has previously been subject to oil and gas activity it is assumed the

r potential for such sites to be present is low. Should a feature be Unlikel y identified, then mitigation measures will be revisited to ensure that Ver N ------9.5 Low Low Mino the site is not disturbed.

REPORT REF: GALIA ES D/4127/2011 A-47 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Appendix B Oil Spill Modelling

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX B-1 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

B.1 Introduction

This report is to support the Environmental Statement for the Galia Development Area (DECC ref no. D/4127/2011) and to meet the latest guidance from the Department of Energy and Climate Change (DECC). The guidance states that the ES assessment of potential impacts from hydrocarbon releases must be extended to match the scope of the recently amended oil pollution emergency plan (OPEP) guidelines.

B.2 Galia Field Development

The Galia Field development is a small development located in the UKCS Block 30/24, in the Central North Sea (CNS). It lies in water depths of approximately 80m and is 280km east of the nearest landfall on the UK coastline and 22km west of the UK/Norwegian international boundary (median line). Nearby fields include Orion and Auk (to the north-west) and Flora, Fife and Angus (to the south-east). One well will be drilled as part of the field development. The coordinates for the well are provided in Table B-1 below. Drilling will be conducted from a semi- submersible mobile drilling unit (MoDU). EnQuest plan to use the Ocean Princess semi-sub MODU at Galia. If it is not available, a semi-submersible with a similar specification could be used. Table B-1: Project co-ordinates Structure Easting (E) Northing (N) Latitude (N) Longitude (E) Proposed Galia drill centre - vertical well 480 340 6 227 140 56° 11' 24.019" 2° 40' 59.636" (GAL-1) Proposed Galia drill centre – directional 480 775 6 227 015 56° 11' 11.307" 2° 41' 24.971" well (GAL-2) Proposed Galia relief well (GAL-RW) 479 986 6 227 056 56° 11' 12.516" 2° 40' 39.199" Datum: WGS84 The drill centre will be tied-back to the Alma production manifold (northern drill centre) and will be produced back to the EnQuest Producer (formerly known as the Uisge Gorm) floating, production, storage and offloading (FPSO) vessel. One new 5.3km, 10-inch buried production flowline, chemical umbilical and a power cable will be installed. A shuttle tanker will visit the FPSO once every two weeks to offload crude oil via a loading hose and tanker mooring system. EnQuest will submit an addendum to the Alma drilling oil pollution emergency plan (OPEP) to the DECC Offshore Inspectorate for approval to cover the drilling activities at the Galia Field. A separate field OPEP will be submitted to the DECC to cover the operational phase of the combined Alma and Galia developments. The OPEPs will comply with the requirements of The Offshore Installations (Emergency Pollution Control) Regulations 2002 and The Merchant Shipping (Oil Pollution Preparedness, Response Co-operation Convention) Regulations 1998 and take into consideration recent revised guidance from the DECC following the Gulf of Mexico Macondo incident.

B.3 Worst Case Oil Spill Modelling

Four scenarios have been identified within the project scope as potential sources for a major spill of hydrocarbons:

REPORT REF: GALIA ES D/4127/2011 B-2 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Loss of diesel inventory from the FPSO and tanker through collision – 2,016 tonnes (2,400m3) from the FPSO and 2,881 tonnes (3,430m3) from the export tanker

Loss of crude oil inventory from the FPSO and tanker through collision – A maximum of 81,0901 tonnes (94,500m3) from the FPSO and a maximum of 87,000 tonnes (100,000m3) from the export tanker (note: neither vessel will be full at the same time) 3 Loss of well control (blow out) - 29,873 tonnes (35,775m ) for 15 days 3 Loss of diesel inventory from the drilling rig – 1,399 tonnes (1,665m ) The most recent UK guidance on oil pollution emergency response requires Operators to model a loss of well control (blow out), as this although an extremely rare occurrence in the UK is considered to be the worst case volume of crude oil that could be spilt from a development. A loss of well control (blow out) would result in a spill of 1,992 tonnes (2,385m3) of crude oil per day. Over the 15 day period the modelling is run for this would result in a spill of 29,873 tonnes (35,775m3) of crude oil. The tie-back of the Galia well to the FPSO via the Alma production centre will not result in any changes to the modelling for the worst case scenario during production of a full loss of containment from both the FPSO and export tanker due to collision (with each other). If this were to happen, a maximum of 4,897 tonnes (5,830m3) of diesel and 87,000 tonnes (100,000m3) of crude oil would be released instantaneously. The 87,000 tonnes of crude oil represents the maximum (larger) capacity of the export tanker as neither vessel will be full at the same time. Full details of the modelling undertaken for this scenario are included in the Alma ES. Modelling has not been undertaken for a loss of diesel inventory for the drilling rig as this is significantly less than the diesel inventory of the export tanker which is considered to be the worst case spill scenario. Oil Spill Response Limited (OSRL) was commissioned to undertake oil spill modelling of these scenarios using OSIS 5.0 software (OSRL 2011). The Oil Spill Information System (OSIS), developed by BMT Cordah Ltd, is an oil spill model that predicts the movement of oil on the water surface and the distribution of oil in the marine environment. It is a fully validated and calibrated oil spill model based upon extensive research conducted by Warren Spring Laboratories and subsequently AEA Technology plc. The weathering model within OSIS has been validated against controlled actual spills at sea and real spill events supported with laboratory calibration. The model has a number of limitations that should be considered when interpreting the results:

Modelling results are for guidance purposes only and response strategies should not be based solely on modelling results alone.

The resolution / quality of tidal and oceanic current data vary between regions and models. As with any other model, results are dependent on the quality of the environmental parameters and scenario inputs used.

The properties of the oil in the model’s database may not precisely match those of the product spilled.

REPORT REF: GALIA ES D/4127/2011 B-3 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

If the same scenario was conducted in another oil spill modelling programme, with identical parameters and inputs, the results may show a degree of variance. This is expected as the different fate and weathering models have been developed and programmed independently. In addition the following assumptions were made when commissioning the models:

A ‘worst case’ air temperature of -6°C and sea temperature of 6°C were used as representative of temperatures in January to depict the fate of the spilled oil in its most viscous and persistent form.

Wind data was taken from the Met Office European model (56.0°N 3.14°E Jan 1998 - Nov 2008). The January wind rose selected as the closest representative example was compiled from a historical data set sourced by the Admiralty from the UK Met Office and covers a period between 1998 and 2008.

The principal tidal current data used was taken from http://www.visitmyharbour.com/articles/article.asp?arturn=1314.

The oils specified for modelling were marine diesel and Duncan crude. Duncan crude is not in the OSIS oil database but oil matching was undertaken to find suitable substitute oil within the OSIS database. Auk has a similar density (API 38.16), specific gravity (0.834) and geographical location to the Duncan crude (API 38 and SG 0.835) and so was selected as the most appropriate oil. Although the estimated time to mobilise and drill a relief well is 90 days, modelling using the OSIS software is not possible for this duration. Instead the model was run for a period of 15 days, which for planning purposes is believed to be more than sufficient. It is likely that beaching will occur within this period for the worst case scenarios in the UKCS (depending upon the oil type, meteorological conditions and location of the spill release point).

B.4 Spill Scenarios and Modelling Results

In accordance with the DECC guidelines on oil spill modelling for OPEPs, the scenarios were modelled using two types of models: Stochastic - A stochastic model, also known as a probability model shows the probability of where an oil spill may impact for defined periods of time for a range of prevailing wind directions. It represents the combination of spills from twelve different wind directions (this means that it does not represent the full extent of a given spill scenario). The model uses historical wind data to run a series of trajectories for the various wind directions. It then combines the results to produce an overall illustration of the probability of where oil might travel to in the defined period of time. This type of modelling is an important tool for determining the areas of coastline that could potentially be affected by a spill and therefore the best locations to place oil spill response equipment. Trajectory - A trajectory or deterministic model are used to predict the route of an oil slick over time and under certain metocean conditions. UK legislation requires two trajectory models are undertaken for each spill scenario investigated by the oil and gas industry; one trajectory using a 30 knot wind blowing towards the nearest stretch of UK coastline; and one trajectory using a 30 knot wind blowing towards the closest international boundary.

REPORT REF: GALIA ES D/4127/2011 B-4 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

For the Galia development one stochastic and two trajectory models were commissioned for the loss of well control spill scenario. The worst case spill scenarios for the total loss of containment from the FPSO/export tanker were taken from the Alma ES (DECC Reference: D/4110/2011). The scenarios and volumes modelled are presented in Table B-2 below. Table B-3 presents a summary of the fates of the spills as illustrated in Figures B-1 to B-9. For the trajectory models, the red lines show the direction of the leading edge of the spill where as the black dots show the areas which the oil is likely to spread to. Table B-2: Spill scenarios modelled Model run Scenario Hydrocarbon Type of spill Quantity (m3) Conditions type 1 Stochastic N/A 2 Loss of well Trajectory 30 knot onshore wind (towards UK) Crude oil control for 15 35,775m3 30 knot offshore wind (towards days 3 Trajectory nearest international boundary e.g. UK/Norway) 4 Stochastic N/A Loss of entire 5 inventory e.g. 100,000 Trajectory 30 knot onshore wind (towards UK) Crude oil during a (Instantaneous) 30 knot offshore wind (towards 6 collision Trajectory nearest international boundary e.g. UK/Norway) 7 Stochastic N/A 8 Trajectory 30 knot onshore wind (towards UK) Loss of entire 5,830 Diesel 30 knot offshore wind (towards inventory (Instantaneous) 9 Trajectory nearest international boundary e.g. UK/Norway)

Table B-3: Modelling results Scenario Model run type Fate of spill, as modelled

Figure B-1 Depending on the prevailing wind conditions at the time of the spill, there is a1% chance of oil beaching along the coastlines of one of the countries that border the North Sea. Modelling 1 Stochastic indicates that the spill will have naturally dispersed within the water column or beached within 417 days. There are numerous protected sites that could be affected by a spill of this size (see Section 8.6 for assessment). Figure B-2 There is potential for crude oil to beach on the north Yorkshire coastline within 8 days and 10 Trajectory hours of the incident. Modelling indicates that approximately 11,118m3 would beach, 2 towards UK 14,986m3 will evaporate and 18,575m3 will disperse naturally. On this trajectory possible beaching locations are within the Teesland and Cleveland Coast Ramsar site and the Beast Cliff - Whitby (Robin Hood’s Bay) SAC protected area. Figures B-3 There is potential for the spill to cross the UK/Norway international boundary (median line) Trajectory within 9 hours of the incident. On this trajectory the spill path will continue and cross the towards closest Norway/Denmark median line within 28 hours of the incident. Modelling indicates that 3 international approximately 30,931m3 (emulsified) of crude oil could beach on the Danish coast after 5 boundary days and 17 hours. It is estimated that approximately 15,224m3 will evaporate and 14,374m3 will disperse naturally within the water column. On this trajectory possible beaching locations are within numerous protected areas along the Danish coastline (see Figure 8-3).

REPORT REF: GALIA ES D/4127/2011 B-5 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Scenario Model run type Fate of spill, as modelled

Figure B-4 Depending on the prevailing wind conditions at the time of the spill, there is a1% chance of oil beaching along the coastlines of one of the countries that border the North Sea. Modelling 4 Stochastic indicates that the spill will have naturally dispersed within the water column or beached within 417 days. There are numerous protected sites that could be affected by a spill of this size (see Section 8.6 for assessment). Figure B-5 There is potential for crude oil to beach on the north Yorkshire coastline within 8 days and 10 Trajectory hours of the incident. Modelling indicates that approximately 86,393m3 would beach, 5 towards UK 38,972m3 will evaporate and 43,750m3 will disperse naturally. On this trajectory possible beaching locations are within the Teesland and Cleveland Coast Ramsar site and the Beast Cliff - Whitby (Robin Hood’s Bay) SAC protected area. Figures B-6 There is potential for the spill to cross the UK/Norway international boundary (median line) within 5 hours of the incident. On this trajectory the spill path will continue and cross the Trajectory Norway/Denmark median line within 31 hours of the incident. Modelling indicates that towards closest 6 approximately 161,742m3 (emulsified) of crude oil could beach on the Danish coast after 5 international days and 12 hours. It is estimated that approximately 35,166m3 will evaporate and 32,486m3 boundary will disperse naturally within the water column. On this trajectory possible beaching locations are within numerous protected areas along the Danish and Norwegian coastlines (see Figure 8-4). Figures B-7 Modelling indicates that it is unlikely that the spill will beach on the coastline. The leading 7 Stochastic edge of the spill travels 6 miles from the Alma development after 10 hours. This is still 171 miles from shore. It is estimated that 2,086m3 will evaporate and 3,744m3 will disperse naturally in the water column (none will beach). Figures B-8 Modelling indicates that on this trajectory it is unlikely that the spill will beach on the UK Trajectory 8 coastline. The leading edge of the spill travels 6 miles from the Alma development after 10 towards UK hours. This is still 171 miles from shore. It is estimated that 2,086m3 will evaporate and 3,744m3 will disperse naturally in the water column (none will beach). Figures B-9 Trajectory Modelling indicates that on this trajectory it is unlikely that the spill will beach on a coastline. towards closest 9 The leading edge of spill travels 20 miles from the Alma development after 10 hours and will international cross the UK/Norway median line within 6 hours. It is estimated that 2,235m3 will evaporate boundary and 3,595m3 will disperse naturally (none will beach).

REPORT REF: GALIA ES D/4127/2011 B-6 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure B-1- Scenario 1-Worst case crude oil spill of 35,775m3 Wind rose

Key for stochastic output

REPORT REF: GALIA ES D/4127/2011 B-7 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure B-2-Scenario 2- Worse case crude oil spill trajectory with 30 knot wind towards the UK

REPORT REF: GALIA ES D/4127/2011 B-8 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure B-3-Scenario 3- Worse case crude oil spill trajectory with 30 knot wind towards the closest international boundary (and Denmark)

REPORT REF: GALIA ES D/4127/2011 B-9 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure B-4- Scenario 1-Worst case crude oil spill of 100,000m3 Wind rose

Key for stochastic output

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Figure B-5-Scenario 2- Worse case crude oil spill trajectory with 30 knot wind towards the UK

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Figure B-6-Scenario 3- Worse case crude oil spill trajectory with 30 knot wind towards the closest international boundary (and Denmark)

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Figure B-7- Scenario 4- Instantaneous diesel spill of 5,830m3

Key for wind rose

REPORT REF: GALIA ES D/4127/2011 B-13 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Figure B-8- Scenario 5- Worst case diesel spill trajectory with 30 knot wind towards the UK

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Figure B-9- Scenario 6- Worst case diesel spill trajectory with 30 knot wind towards the closest international boundary

REPORT REF: GALIA ES D/4127/2011 B-15 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

B.5 Environmental Impact Assessment

B.5.1 Seabirds

A diesel spill will rapidly evaporate on release and will naturally disperse in the high energy offshore environment. Modelling, presented in Figures B-7, B-8 and B-9, indicates that a diesel spill of 5,830m3 i.e., from a combined loss of inventory from the FPSO and export tanker, will naturally disperse and evaporate within 10 hours. As such, it is not considered that diesel will pose a significant threat to seabirds. There is the potential that seabirds could be significantly affected if a large crude oil spill was to occur. The worst case scenarios modelled i.e., loss of well control and a loss containment from both the FPSO and export tanker due to collision, has the potential to affect a large area of the marine environment and depending on the prevailing wind condition at the time beach on the coastline of one of the countries bordering the North Sea. These results of the modelling area provided in Table B-2 above. A spill of the magnitudes modelled above is likely to significantly impact populations of seabirds. Seabirds that spend majority of the time on sea surface are most vulnerable as birds can be smothered by oil or their feathers can become contaminated with hydrocarbons, which in turn may be ingested. Seabird vulnerability to hydrocarbon pollution is highest in January and October. As the drilling rig will be on-site from July 2011 until November 2013 (Galia only), there will be overlap with the sensitive periods for seabirds. In addition, the FPSO will offload crude oil every two weeks throughout the year and therefore at some point each year operations will overlap with the sensitive periods identified. In the event of a spill occurring, the required intervention response will be implemented to minimise the risk of smothering and species injury.

B.5.2 Marine Mammals

There is potential for marine mammals to be significantly affected if a large crude oil spill was to occur. Although the region surrounding the Galia development is not considered to be particularly important for marine mammals, pods and individuals have been observed throughout the year. Should a major release of crude oil occur, there is potential for individuals to be affected. In addition should any oil reach the shoreline, haul-out sites for pinnipeds may be impacted. Pinnipeds are particularly sensitive between October and January when they are on land pupping and again between February and March during their annual moult. Neonatal pups are particularly at risk from oil coming ashore. Cetaceans have smooth hairless skins over a thick layer of insulating blubber, so oil is unlikely to adhere persistently or cause a breakdown in insulation. Marine mammals must surface to breathe and they may inhale vapours given off the spilt oil and their eyes may be vulnerable to major pollution. Indirect effects may also be caused through contamination and depletion of food resources.

REPORT REF: GALIA ES D/4127/2011 B-16 02/05/2012 ENQUEST HEATHER LIMITED GALIA FIELD DEVELOPMENT

Due to the transient nature of cetaceans, it is likely that individuals not in the immediate area of the spill when it occurs will avoid the area and it is possible that the number of individuals affected could be small. However, if a substantial number of a population where affected there could be knock on effects to breeding and the long-term viability of the population. Recovery rates of land based marine mammals such as seals could be longer particularly if a spill affected a breeding season.

B.5.3 Protected Sites

There is potential for protected sites and species to be significantly affected if a large crude oil spill was to occur. Although there are no designated protected sites within 40km of the Galia field a major crude oil spill (from either loss of well control or loss of inventory) could beach on the coastline as summarised in Table B-2 and Figure B-1 and Figure B-4. Modelling indicates that the probability of either spill scenario beaching is 1%. There are numerous coastal and marine protected sites designated along the coast of the North Sea that could be affected. These are illustrated in Figure 8- 3 and Figure 8-4. Should a spill occur that could potentially affect a protected area an intervention response would be required.

B.6 References

OSRL (2011). Oil Spill Modelling for Galia Field Development. Prepared for Intertek METOC. Project Number 4558/15.

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Appendix C Summary of Chemicals

REPORT REFERENCE: GALIA ES D-4127-2011.DOCX C-1 02/05/2012 ENQUEST BRITAIN LIMITED GALIA FIELD DEVELOPMENT

Please note: All chemicals provided in the following tables are for one well (five sections) and one well tie-in only. Full chemical requirements will be confirmed in the relevant PON15B or PON15C chemical permit application to be submitted to the DECC at least 28 days before operations start. Chemicals to be used on the FPSO had not been confirmed at the time of ES submission but will be included in a PON15D chemical permit. This will be available for public review approximately 2 months prior to production operations commencing.

C.1 Drilling Chemicals

C.1.1 36" Section

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) Caustic Soda E 0.60 0.60 DEFOAM NS Gold SUB 4.00 4.00 Drispac® Plus Superlo ™ Polymer E PLO 6.39 6.39 DUO-TEC Gold 3.00 3.00 DUO-VIS Gold 3.00 3.00 GUAR GUM E PLO 20.00 20.00 Lime E PLO 1.00 1.00 M-I BAR (All Grades) E PLO 210.00 210.00 M-I Gel E PLO 72.00 72.00 Mica E PLO 2.00 2.00 Nutshells (All Grades) E PLO 2.00 2.00 POLYPAC (All Grades) E PLO 4.10 4.10 SAFE-CIDE Gold 1.10 1.10 SAFE-SCAV HSB Silver 1.00 1.00 Soda Ash E PLO 0.60 0.60 Sodium Bicarbonate E PLO 2.00 2.00

C.1.2 26" Section

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) Caustic Soda E 0.60 0.60 DEFOAM NS Gold SUB 4.00 4.00 Drispac® Plus Superlo ™ Polymer E PLO 6.39 6.39 DUO-TEC Gold 3.00 3.00 DUO-VIS Gold 3.00 3.00 GUAR GUM E PLO 20.00 20.00 Lime E PLO 1.00 1.00 M-I BAR (All Grades) E PLO 210.00 210.00 M-I Gel E PLO 72.00 72.00 Mica E PLO 2.00 2.00 Nutshells (All Grades) E PLO 2.00 2.00

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Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) POLYPAC (All Grades) E PLO 4.10 4.10 SAFE-CIDE Gold 1.10 1.10 SAFE-SCAV HSB Silver 1.00 1.00 Soda Ash E PLO 0.60 0.60 Sodium Bicarbonate E PLO 2.00 2.00

C.1.3 17 ½" Section

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) CAUSTIC SODA E 5.40 5.40 Citric Acid E PLO 4.00 4.00 DEFOAM NS Gold SUB 4.00 4.00 DRILLING STARCH E PLO 3.00 3.00 Drispac® Plus Superlo ™ Polymer E PLO 19.17 19.17 DUO-TEC Gold 7.75 7.75 DUO-VIS Gold 4.00 4.00 Dynared ™ Seepage Control Fiber E PLO 8.00 8.00 GLYDRIL MC Gold 20.00 20.00 G-SEAL PLUS E PLO 6.00 6.00 GUAR GUM E PLO 19.00 19.00 KWIK-SEAL (All Grades) E 6.00 6.00 Lime E PLO 1.00 1.00 M-I BAR (All Grades) E PLO 450.00 450.00 M-I GEL E PLO 460.00 460.00 Nutshells (All Grades) E PLO 2.00 2.00 POLYPAC (All Grades) E PLO 8.15 8.15 POTASSIUM CHLORIDE E PLO 6.00 6.00 Potassium Chloride brine E PLO 20.00 20.00 SAFE-CARB (All Grades) E PLO 15.00 15.00 SAFE-CIDE Gold 1.10 1.10 SAFE-SCAV HSB Silver 1.00 1.00 SAPP E PLO 2.00 2.00 SODA ASH E PLO 5.40 5.40 Sodium Bicarbonate E PLO 4.00 4.00

REPORT REF: GALIA ES D/4127/2011 C-3 02/05/2012 ENQUEST BRITAIN LIMITED GALIA FIELD DEVELOPMENT

C.1.4 12 ¼" Section

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) BENTONE 920 E 18.86 0.00 Calcium Chloride (All Grades) E PLO 24.36 0.00 CAUSTIC SODA E 1.00 0.00 Citric Acid E PLO 4.00 0.00 DF1 E 500.39 0.00 DUO-TEC Gold 3.00 0.00 DUO-VIS Gold 3.00 0.00 Dynared ™ Seepage Control Fiber E PLO 6.00 0.00 ECOTROL RD E SUB 11.07 0.00 EMI-1017 C 18.15 0.00 FORM-A-SQUEEZE E PLO 8.00 0.00 G-Seal E PLO 16.00 0.00 G-SEAL PLUS E PLO 16.00 0.00 KOPLUS LO Gold 8.00 0.00 KWIK-SEAL (All Grades) E 6.00 0.00 LIME E PLO 28.00 0.00 M-I BAR (All Grades) E PLO 646.60 0.00 Mica E PLO 6.00 0.00 NUTSHELLS (All Grades) E PLO 6.00 0.00 Potassium Chloride E PLO 5.00 0.00 SAFECARB (All Grades) E PLO 50.00 0.00 SAFES-CAV HSB Gold 1.00 0.00 SAFE-SURF E Gold SUB 4.00 0.00 SAFE-SURF NS Gold SUB 6.00 0.00 SAPP E PLO 2.00 0.00 Sodium Bicarbonate E PLO 4.00 0.00 SPERSENE CFI E PLO 5.00 0.00 SUPER SWEEP Gold SUB 1.00 0.00 SWA EH A SUB 4.00 0.00 TRUVIS E 17.34 0.00 Ven-chem 222 E 16.00 0.00 VERSACLEAN CBE B SUB 18.00 0.00 Versaclean FL B SUB 18.00 0.00 Versaclean VB B SUB 18.00 0.00 VERSAGEL HT E 30.00 0.00 VERSATROL E SUB 17.58 0.00 VERSATROL HT D SUB 16.00 0.00 VERSATROL M E SUB 9.00 0.00 VG-SUPREME E 18.09 0.00

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C.1.5 8 ½" Section

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) BENTONE 920 E 18.86 0.00 Calcium Chloride (All Grades) E PLO 26.74 0.00 CAUSTIC SODA E 1.00 0.00 Citric Acid E PLO 4.00 0.00 DF1 E 818.27 0.00 DUO-TEC Gold 3.00 0.00 DUO-VIS Gold 3.00 0.00 Dynared ™ Seepage Control Fiber E PLO 6.00 0.00 ECOTROL RD E SUB 16.88 0.00 EMI-1017 C 30.92 0.00 FORM-A-SQUEEZE E PLO 8.00 0.00 G-Seal E PLO 16.00 0.00 G-SEAL PLUS E PLO 16.00 0.00 KOPLUS LO Gold 8.00 0.00 KWIK-SEAL (All Grades) E 6.00 0.00 Lime E PLO 27.00 0.00 M-I BAR (All Grades) E PLO 906.45 0.00 Mica E PLO 6.00 0.00 NUTSHELLS (All Grades) E PLO 6.00 0.00 Potassium Chloride E PLO 5.00 0.00 SAFECARB (All Grades) E PLO 80.00 0.00 SAFE-SCAV HSB Gold 1.00 0.00 SAFE-SURF E Gold SUB 4.00 0.00 SAFE-SURF NS Gold SUB 6.00 0.00 SAPP E PLO 2.00 0.00 Sodium Bicarbonate E PLO 4.00 0.00 SPERSENE CFI E PLO 5.00 0.00 SWA EH A SUB 4.00 0.00 TRUVIS E 21.06 0.00 Ven-chem 222 E 16.00 0.00 VERSACLEAN CBE B SUB 22.00 0.00 Versaclean FL B SUB 20.20 0.00 Versaclean VB B SUB 20.20 0.00 VERSAGEL HT E 26.58 0.00 VERSATROL E SUB 15.86 0.00 VERSATROL HT D SUB 25.50 0.00 VERSATROL M E SUB 21.50 0.00 VG-SUPREME E 21.56 0.00

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C.2 Cementing Chemicals

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) Barite E PLO 408.16 40.816 Calcium Chloride - Liquid E PLO 15.42 1.542 CEMENT - CLASS G E PLO 948 94.8 CFR-8L Gold 8.52 0.852 ECONOLITE LIQUID E PLO 30.67 3.067 Fluorodye UC Gold 0.12 0.012 GASSTOP LIQUID Gold SUB 8.68 0.868 HALAD-300L NS Gold 22.24 2.224 HR-25L Gold 4.67 0.467 HR-4L E PLO 14.12 1.412 HR-601L NS E PLO 4.61 0.461 MUSOL SOLVENT Gold 11.04 1.104 NF-6 Gold 0.84 0.084 SA-533 Gold SUB 2.04 0.204 SCR-100L Gold 10.71 1.071 SCR-500 L Gold SUB 15.51 1.551 SEM 8 Gold 25.38 2.538 SILICALITE LIQUID E PLO 46.08 4.608 SSA-1 E PLO 333 33.3 TUNED LIGHT XL E 240 24 TUNED SPACER E+ E PLO 20.4 2.04 WellLife 734 E PLO 1.36 0.136

C.3 Completion and Other Chemicals

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) Aqueous Degreaser 2000 Gold SUB 12.00 12.00 Bestolife 3010 ULTRA (version 1) E 6.00 0.60 Calcium Bromide Brine E PLO 2437.96 2437.96 Calcium Chloride Brine E PLO 1991.58 1991.58 Caustic Soda E 2.00 2.00 Celatom Diatomite-All FW Grades E 3.41 0.00 Celatom Perlite-All Grades E 0.29 0.00 Cesium Formate Brine (unbuffered) Gold 12.50 12.50 CLEENOL OD HEAVY DUTY Gold 34.00 34.00 DEFOAM NS Gold SUB 0.40 0.40 DF1 E 763.14 0.00 DI BALANCE E PLO 2.00 0.00 DI TROL E PLO 4.00 0.00

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Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (tonnes) (tonnes) DUAL-FLO Gold 2.00 2.00 DUO-TEC Gold 4.00 4.00 DUO-VIS Gold 4.00 4.00 EB-8035 Gold SUB 2.00 2.00 EMI-1705 C 1.00 0.00 EMR-961 Silver SUB 10.00 0.00 EZEFLO* Surfactant B197 Gold SUB 1.00 1.00 FLO-VIS PLUS Gold 1.00 1.00 HEC E PLO 2.00 2.00 JET-LUBE® RUN N SEAL™ECF E 0.10 0.01 JET-LUBE®SEAL-GUARD™ECF E 0.10 0.01 MAGNESIUM OXIDE E PLO 1.00 1.00 M-I BAR (All Grades) E PLO 300.00 300.00 Monoethylene Glycol E PLO 10.00 10.00 Potassium Formate Brine E PLO 115.40 115.40 SAFE COR 220X Gold 16.00 16.00 SAFE-CARB (ALL GRADES) E PLO 12.00 12.00 SAFE-CIDE Gold 2.00 2.00 Safe-Cor HT C 0.82 0.82 SAFE-SCAV CA Gold 8.00 8.00 SAFE-SCAV HSB Silver 2.00 2.00 SAFE-SCAV NA E PLO 8.00 8.00 SAFE-SURF E Gold SUB 8.00 8.00 SAFE-SURF NS Gold SUB 18.00 18.00 SI-414N Gold 3.00 3.00 Sodium Chloride Brine E PLO 1991.58 1991.58 Stack-Magic ECO-F v2 D 12.00 12.00 System Cleaner G D 0.04 0.04

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C.4 Pipeline Chemicals

Chemical Name HQ Chemical Estimated Use Estimated Discharge Label (kgs) (kgs) Castrol Transaqua HT2 D 0 101.6 DYESTICK RX-9034A Gold 0.4 0.25 MEG E PLO 445.2 1227.2 RX-9022 Gold 23.6 17.8 RX-5227 Gold 103.4 81.4

Note: Chemical discharge exceeds chemical use as some sections of spool piece or chemical umbilical are pre-filled onshore.

C.5 Summary of Discharges from Well Tie-In

Chemical Name Estimated Use Estimated Estimated Fate Chemical (onshore pre-fill) Use Discharge HQ Label (kg) (offshore) (kg) (kg) Castrol 27.52 0 27.52 Discharged at seabed D Transaqua HT2 DYESTICK RX- 0 0.25 0.25 Discharged via FPSO Gold 9034A process system MEG 782 445.2 1227.2 Discharged via FPSO process system or E PLONOR discharged at sea surface from DSV RX-9022 0.072 1.06 1.132 Discharged via FPSO process system or Gold discharged at sea surface from DSV

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Appendix D Institutional Policy and Regulatory Framework

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D.1 Relevant Policy Guidelines

ƒ Energy White Paper 2007 and the UK Low Carbon Transition Plan 2009 – Sets out the UK Governments international and domestic energy strategy to respond to the changing circumstances in global energy markets and to address the long term energy challenges the country faces (DTI 2007, HM Government 2009).

ƒ Marine Policy Statement – UK Government and devolved administrations have worked together to set out a number of high level marine objectives which articulate the outcomes they are seeking for the UK marine area as a whole. Their vision is to achieve clean, healthy, safe, productive and biologically diverse oceans and seas. The Department for Environment, Food and Rural Affairs (Defra) are responsible for developing this strategy. It sets out the general environmental, social and economic considerations that need to be taken into account in marine planning. Consultation on the Statement and supporting documents has been ongoing since 2008 and the Marine Policy Statement was adopted in March 2011 (Defra 2011). ƒ UK Biodiversity Action Plan (UK BAP) – The UK BAP is the UK Government’s response to the Convention on Biological Diversity (CBD) (1992). It describes the UK’s biological resources and provides detailed plans for the protection of these resources. In 2007 the UK BAP list was reviewed and now includes 1,150 species and 65 habitats. Action plans, which set out priorities, actions, targets and reporting targets, have been created for 382 species and 45 habitats.

D.2 International Conventions, EC and UK Laws and Regulations

D.2.1 International Conventions

ƒ Convention for the Protection of the Marine Environment of the North East Atlantic (Oslo Paris Convention (OSPAR) Convention) 1992 – main legislative instrument regulating international cooperation. It concentrates on provisions to protect the marine environment through the use of best available techniques, best environmental practice and where appropriate clean technologies (OGUK 2008). The precautionary principle concept also features prominently. The convention regulates European standards on the offshore oil and gas industry, marine biodiversity and baseline monitoring of environmental conditions (OGUK 2008). As a signatory to the Convention, the UK, and therefore the UK oil and gas industry and this project, are governed by the legislative framework the Convention enforces. For example, the OSPAR convention prohibits the discharge of oil based mud (OBM), which determines how drill cuttings are managed during a drilling operation. ƒ Convention on Biological Diversity (CBD) 1992 – this international treaty sets out commitments for maintaining the world's ecological biodiversity as the world develops. The Convention establishes three main goals: the conservation of biological diversity, the sustainable use of its

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components, and the fair and equitable sharing of the benefits from the use of genetic resources. UK Government has reacted to the commitments of the Convention by establishing the UK BAP discussed in Section 2.1. ƒ United Nations Framework Convention on Climate Change (1994) - The Convention sets an overall framework for intergovernmental efforts to tackle the challenge posed by climate change. It recognises that the climate system is a shared resource whose stability can be affected by industrial and other emissions of carbon dioxide and other greenhouse gases. Under the Convention the Government is committed to gather and share information on greenhouse gas emissions and launch national strategies for addressing greenhouse gas emissions (UNFCCC 2008). The convention has also influenced EC and UK legislation, being pivotal in the establishment of the EC Council Directive 2003/87/EC and the UK Greenhouse Gas Emissions Trading Scheme Regulations, discussed in Sections 2.2.2 and 2.2.3. ƒ Convention on Environmental Impact Assessment in a Transboundary Context (Espoo) 1991 – The Espoo Convention sets out the obligations of Parties to assess the environmental impact of certain activities at an early stage of planning. It also lays down a general obligation to States to notify and consult each other on all major projects under consideration that are likely to have a significant adverse environmental impact across boundaries. The Convention was adopted in 1991 and entered into force in 1997. D.2.2 EC Law

The European Commission issues directives, regulations, decisions, opinions and recommendations (see glossary for definitions) to member states. The above cover all aspects of society from culture, technology and human rights to the environment, wildlife and nature conservation. The development will be subject to a wide range of Directives and Regulations as they are implemented in UK law. A number of the key Directives are listed below:

ƒ Council Directive 97/11/EC (EIA Directive) – Amended Directive 85/337/EC on the assessment of the effects of certain public and private projects on the environment. Requires environmental assessments to be carried out for certain types of offshore oil and gas activities. ƒ Council Directive 2003/35/EC (Public Participation Directive) – provides for public participation in respect of the drawing up of certain plans and programmes relating to the environment and amending with regard to public participation and access to justice Council Directive 85/337/EC. ƒ Council Directive 2001/42/EC (SEA Directive) – The purpose of the Strategic Environmental Assessment (SEA) Directive is to ensure that environmental consequences of certain plans and programmes are identified and assessed during their preparation and before their adoption. This will mean that environmental assessments carried out for individual projects will be able to take advantage of additional data and information on the regional impacts of the oil and gas industry.

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ƒ Council Directive 92/43/EC (Habitats Directive) – Directive on the conservation of natural habitats and wild fauna and flora. The Directive introduces a range of measures to protect 189 habitats and 788 species listed in the Annexes. Each member state is also required to prepare and propose a national list of sites to be adopted as Special Areas of Conservation (SACs). ƒ Council Directive 79/409/EC (Birds Directive) – The Directive provides a framework for the conservation and management of, and human interactions with, wild birds in Europe. Like the Habitats Directive it introduces a range of measures to maintain the favourable conservation status of all wild bird species across their distributional range and allows for the establishment of Special Protection Areas (SPAs) for rare or vulnerable species. ƒ Council Directive 2008/1/EC (Integrated Pollution Prevention and Control (IPPC) Directive) – replaces Directive 96/61/EC and aims to prevent and control emissions to air, water and soil from industrial installations. The directive aims to increase the use of best available techniques (BATs), to ensure a higher level of environmental protection. ƒ Council Directive 2003/87/EC (EU Emissions Trading Scheme (EU ETS) Directive) – The Directive establishes a scheme for greenhouse gas emissions allowance trading within the European Community. The Directive requires that member states establish national allocation plans for emissions. ƒ Registration, Evaluation, Authorisation and restriction of Chemicals (REACH) - Applies to substances manufactured or imported into the EU in quantities of 1 tonne or more per year. Aims to protect human health and the environment from chemical use. ƒ OSPAR Recommendation 2010/5 on the assessment of environmental impacts on threatened and/or declining species – Requires that Contracting Parties to OSPAR take into consideration the relevant species and habitats on the OSPAR List of threatened and/or declining species and habitats when assessments of environmental impacts of human activities that may affect the marine environment of the OSPAR maritime area are prepared. D.2.3 UK Law

Although not an exhaustive list, the main UK regulations applying to the project are listed below:

ƒ Petroleum Act 1998 – Requires all offshore oil and gas development to apply for consent to undertake the project. Consent is issued by the Secretary of State (SoS) and in addition to giving consent to construct the development authorises the owners to operate the development. ƒ Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007 – amend the 1999 regulations of the same name. The regulations implement the EC EIA Directive and Public Participation Directive; requiring an ES to be

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submitted for offshore oil and gas projects and public participation in the consent process. ƒ Offshore Petroleum Activities (Conservation of Habitats) Regulations 2001 (amended in 2007) – The regulations apply the Habitats Directive and Birds Directive in relation to oil and gas projects on the UKCS. ƒ Offshore Marine Conservation (Natural Habitats, &c.) Regulations 2007 (as amended in 2009 and 2010) – These regulations apply in the offshore area of the UK and protect marine species and wild birds through a number of offences that aim to prevent environmentally damaging activities. It is now an offence under the Regulations to deliberately disturb wild animals of a European Protected Species. The regulations also implement in the UK the EC Directives 92/43/EC (Habitats Directive) and 79/409/EC (Birds Directive). ƒ Offshore Petroleum Activities (Oil Pollution Prevention and Control) Regulations 2011 – The regulations are designed to encourage operators to reduce the quantities of hydrocarbons discharged during the course of offshore operations. ƒ Offshore Chemical (Amendment) Regulations 2011 – Requires all offshore operators using and/or discharging chemicals to apply for a chemical permit. With respect to the project this will take the form of Petroleum Operators Notices (PONs) for the drilling (PON15B) and pipeline (PON15C) which will be submitted to the Department of Energy and Climate Change (DECC) in advance of operations. ƒ Merchant Shipping (Oil Pollution Preparedness, Response Co-operation Convention) Regulations 1998 – Under these regulations operators of offshore oil and gas installations and pipelines must have an approved oil pollution emergency plan (OPEP) setting out arrangements for responding to incidents which cause or may cause marine pollution by oil, with a view to preventing such pollution or reducing or minimising its effect. ƒ The Offshore Installations (Emergency Pollution Control) Regulations 2002 – The Regulations give the UK Government powers to intervene in the event of an incident or accident involving an offshore installation where there is, or may be risk of, significant pollution, or where the operator is failing or has failed to implement effective control and preventative operations. ƒ The Greenhouse Gas Emissions Trading Scheme Regulation 2005 – provide a framework for a greenhouse gas emissions trading scheme and implement EC Directive 2003/87/EC. Any installation with combustion plant that on its own or in aggregate with any other combustion plant has a rated thermal input exceeding 20MW(th) is required to be registered under the EU ETS. ƒ The Offshore Combustion Installations (Prevention and Control of Pollution) (Amendment) Regulations 2007 – The regulations implement EC Directive 96/61/EC and apply to combustion installations located on offshore oil and gas platforms where an item of combustion plant on its own, or together with any other combustion plant installed on a platform, has a rated thermal input exceeding 50MW(th).

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ƒ Marine and Coastal Access Act (MCAA) 2009 – The Act seeks to improve management and increase protection of the marine environment. It is a large Act that covers a multitude of provisions. Amongst other things it establishes a new Marine Management Organisation, to produce marine plans, administer marine environmental licensing, enforce environmental protection law and manage marine fisheries, and introduces new mechanisms for the designation of marine conservation zones. ƒ Energy Act 2008 – The provisions of the Coast Protection Act relating to navigation considerations regarding the oil and gas industry were transferred to the Energy Act in April 2011 by the MCAA. The change introduces a formal application process linked the environmental regime for consent to locate fixed infrastructure e.g., pipelines, platforms, wellheads, drilling rigs etc. It will also apply to some vessel activities if the vessel is physically connected to the seabed that could constrain their ability to navigate e.g., drill ships and intervention vessels. ƒ The Merchant Shipping (Prevention of Pollution by Sewage and Garbage from Ships) Regulations 2008 – The regulations implement in the UK the requirements of MARPOL 73/78 Annex IV. It should be noted that MARPOL also defines a ship to include fixed and or floating platforms and these are required where appropriate to comply with the requirements similar to those set out of vessels.

D.3 SEA and EIA Guidelines

The DECC have issued guidance notes regarding the Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) (Amendment) Regulations 2007, providing details of the required contents of an ES. This ES takes into account this latest guidance (DECC 2009a). In addition, the DECC has recently released a statement in a letter to industry (23 December 2010) stating that the ES assessment of potential impacts from hydrocarbon releases must be extended to match the scope of the recently amended OPEP guidelines. The EIA process is designed to consider the potential impacts from an individual project, ignoring those from other activities in the area. Although consideration is now being given to cumulative impacts in EIA this is still project specific. As a result of the limitations of the EIA process there is now a push towards using EIA at a more strategic stage of the industry development phase. SEAs consider environmental objectives at policy and planning stages, provide a common basis for EIA preparation and ensures that total activity level in one region does not impose unacceptable regional environmental impacts. In 2001 the EC adopted a Directive on the assessment of the effects of certain plans and programmes on the environment 2001/42/EC (SEA Directive). Although the UK have yet to formally implement this Directive, the DECC has produced a series of SEAs for regions of the UKCS. This project lies within SEA region 2. Once SEAs were completed for all regions of the UKCS an Offshore Energy SEA was undertaken in 2008/2009 to inform further seaward rounds of oil and gas licensing, future licensing for the underground storage of combustible gas in depleted and other offshore oil and/or gas fields and further rounds of offshore wind farm leasing. This OESEA was updated with

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amendments issued in 2011. The technical reports and recommendations made in all of these SEAs were used to inform this EIA.

D.4 UK Institutional Framework

ƒ Secretary of State (SoS) – The ES review and approval process culminates in an approval from the SoS under the Petroleum Act 1998. The SoS is also the focal point for appeals to decisions. The SoS leads the DECC. ƒ Department for Energy and Climate Change (DECC) – Administers the Petroleum Act 1998 under which project consents are given. They are the principal environmental regulator for the offshore oil and gas industry and are responsible for implementation of the EIA Regulations. They also have representatives at OSPAR as a Regulatory Authority. ƒ Department for Environment Food and Rural Affairs (Defra) – Responsible for implementation of Government programmes for the protection of the environment, food (including fisheries) and rural affairs. At the European and international level Defra represent the UKs interests at OSPAR. The department provides advice to the DECC on a range of subjects including: environmental statements, the interactions between fisheries and offshore operations, offshore construction and drilling activities, marine pollution and chemical use and discharge. In Scotland many of the advisory responsibilities for the offshore oil and gas industry are delegated to Marine Scotland. ƒ Joint Nature Conservation Committee (JNCC) – Responsible for promoting nature conservation at UK and international levels. They are the main government and industry advisor on offshore sensitivities with respect to seabirds and cetaceans. Amongst other roles they advise the DECC on environmental statements and are the body responsible for identification and recommendation on offshore conservation areas under the EC Habitat Directive. ƒ Marine Scotland – Is the directorate of Scottish Government responsible for the integrated management of Scotland’s sea. Amongst other roles they advise the DECC on the Offshore Chemical Regulations and impacts on fish and fisheries.

REPORT REF: GALIA ES D/4127/2011 D-15 02/05/2012 Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) Regulations 1999 (as amended by the Energy Act 2008 (Consequential Modifications) (Offshore Environmental Protection) Order 2010) Galia Field Development EnQuest Heather Limited has applied to the Secretary of State for Energy and Climate Change for consent to redevelop the Duncan Field. The field, to be renamed Galia is located 280 km east of the nearest landfall on the UK coastline, 56° 11’ 08.85” N; 02° 41’ 19.53” E. In accordance with the above mentioned Regulations (as amended), this application is accompanied by a PON16 and an Environmental Statement, copies of which may be inspected between 10 a.m. and 4 p.m. on business days at Metoc Ltd, Exchange House, Station Road, Liphook, Hampshire, GU30 7DW until close of business on 29/06/2012. Copies of the Statement may be obtained from Metoc Ltd, Exchange House, Station Road, Liphook, Hampshire, GU30 7DW (**subject to a payment of £2 by P.O. or cheque made payable to Metoc Ltd) or may be downloaded from the Press Releases area at www.metoc.co.uk. Members of the public have until 29/06/2012 to make representations in relation to the application to the Secretary of State for Energy and Climate Change. All correspondence should refer to D/4127/2011. Comments on the statement may be sent in by email, letter or fax and should be marked for the attention of: EIA Co-ordinator Environmental Management Team Energy Development Unit Department of Energy and Climate Change 4th Floor, Atholl House 86 – 88 Guild Street Aberdeen, AB11 6AR Email: [email protected] Fax: 01224 254019 Copies of representations received may be made publicly available. Following receipt of all views and representations the Secretary of State will either grant or refuse consent for the proposal (with or without conditions). Notice of the Secretary of State’s decision will be published in the London, Edinburgh and Belfast Gazettes, and on the Department of Energy and Climate Change, Energy Development Unit website.

Rights of aggrieved persons Within six weeks from the date of publication of the details of the consent or approval, any person aggrieved by the decision may apply to the Court. The Court may grant an order quashing the approval or the granting of consent, where it is satisfied the granting of the approval/consent was done in contravention of the requirement to consider the Environmental Statement, any further information submitted and the representations and comments of environmental authorities and the public. The court may also grant such an order where the interests of the aggrieved person have been prejudiced by a failure to comply with any other requirement of the Regulations. Pending determination of the application by an aggrieved person, the court may by interim order, stay the operation of the consent/approval.