SUPPLY CHAIN CAPACITY REPORT

UKCS DECOMMISSIONING SUPPLY CHAIN CAPACITY REPORT March 218 Produced by 1

CONTENTS EXECUTIVE SUMMARY 4 1 Introduction 8 2 Study findings 2.1 Overall UKCS demand 9 2.2 Platform wells P&A 11 2.3 Subsea wells P&A 14 2.4 Subsea infrastructure removal 18 2.5 Topside removal 24 2.6 Substructure removal 26 2.7 Onshore remediation, dismantling and recycling 29 3 Conclusions 32 4 Recommendations for future studies 33 Appendix Project methodology and approach 34 ABBREVIATIONS CAR Controlled Activities Regulations (License) CNS Central North Sea CoP Cessation of Production CSV Construction Support Vessels DSV Dive Support Vessels EIS East Irish Sea HLV Heavy Lift Vessel IS Irish Sea LWIV Light Well Intervention Vessel MDU Modular Drilling Units MSV Multipurpose Support Vessel NNS Northern North Sea OGA Oil & Gas Authority P&A PBDR PPC PWG ROVSV RSA SE SNS SSCV Te UKCS WML WoS Plugging & Abandonment Platform Based Drilling Rigs Pollution Prevention and Control (Licence) Project Work Group ROV Support Vessel Radioactive Substance Authorisation Scottish Enterprise Southern North Sea Semi-submersible Crane Vessel Metric Tonne United Kingdom Continental Shelf Waste Management License West of Shetland 2 Decommissioning Supply Chain Capacity Report

ACKNOWLEDGEMENTS We would like to acknowledge the Project Work Group (PWG) for their guidance and valuable contributions: Robert McCaig Babcock International Group Heather Woods Decom North Sea Angela McKenzie Decom North Sea Bill Cattanach Oil & Gas Authority Sylvia Buchan Oil & Gas Authority Karen Craig Scottish Enterprise Davi Quintiere Slalom Willem van Es Wood We would also like to thank the industry subject matter experts who contributed to the analysis and the participating companies for taking the time to respond to the survey, providing valuable data to assist with conducting an analysis of supply vs demand for 217. ACKNOWLEDGEMENTS Finally, we would like to thank Decom North Sea, Scottish Enterprise and the Oil & Gas Authority, for commissioning this report. DISCLAIMER This report has been commissioned by, and is intended for, Decom North Sea, Scottish Enterprise and the Oil & Gas Authority, and has been produced by Accenture (UK) Limited (referred to in this report as Accenture or we ). This report has been prepared for information purposes and the information contained in it is based upon data from third party sources, including participants of the Capacity Survey that were identified as focal points by their organisations, memberships or directly by the Project Work Group, or otherwise from the participant s company website. Accenture has relied upon the information provided by participants completing the Capacity Survey in the creation of this report. Where Accenture had reason to believe such information was inaccurate or incomplete, it has taken steps to verify the accuracy of the results of the Capacity Survey, where possible. No responsibility is accepted by Accenture for any inaccuracy or error in the information contained in this Report or any action taken or not taken in reliance on this Report. 3

EXECUTIVE SUMMARY EXECUTIVE SUMMARY The decommissioning of oil and gas infrastructure on the United Kingdom Continental Shelf (UKCS) is an area of activity that is widely expected to increase due to the maturity of the basin. This report, prepared by Accenture and commissioned by Decom North Sea, Scottish Enterprise and the Oil & Gas Authority, sets out the findings to a study conducted to provide a high-level baseline assessment of the current decommissioning capacity to service UKCS decommissioning demand. The following six activity areas were identified for analysis: 1. Platform wells plugging and abandonment 2. Subsea wells plugging and abandonment 3. Subsea infrastructure removal 4. Topside removal 5. Substructure removal 6. Onshore remediation, dismantling and recycling. Demand data was provided by the Oil & Gas Authority (OGA). The data numbered 165 projects and their associated or potential year of Cessation of Production (CoP) which ranged from 211-223. The number of platform and/or subsea wells per project and associated infrastructure tonnage for removal was also given. Capacity to meet demand, referred to as supply data, was established by collating information from a survey questionnaire issued in summer 217 to relevant companies in the supply chain that could provide key assets or equipment to carry out these six key activities. The demand and supply data were analysed to assess the extent to which the supply chain would be able to meet the need for forthcoming decommissioning projects. This created a snapshot in time and provided a baseline of current supply capacity in relation to current anticipated demand. The overall conclusion from this research is that current supply chain capacity appears sufficient, and at times, surplus, to meet estimated demand for decommissioning activities on the UKCS. The industry is, however, subject to evolving macroeconomic and market conditions and has been (and will continue to be) disrupted by forces that go far beyond supply and demand. These external forces may have a significant impact on UKCS decommissioning capacity: Oil price fluctuations Regulatory framework Increasing competition for the UK supply chain New decommissioning-centric technologies and processes 4 Decommissioning Supply Chain Capacity Report

Key observations for the specific activity areas were: Platform Wells P&A 84 platform wells will require P&A based on current potential CoP dates to 223. Overall there appears to be sufficient capacity in 217/18 to meet this potential demand. If activity proceeds as estimated the CNS may experience capacity constraints in 218. The NNS region is likely to be reliant on MDUs for P&A activity due to water constraints associated with jack ups. Platform-Based Drilling Rigs (PBDRs) may be reactivated to carry out platform well P&A and would help to mitigate capacity constraints. Subsea Wells P&A 462 subsea wells will require P&A based on current potential CoP dates to 223. Current supply clearly outstrips potential demand, and the backlog of pre-217 activities could easily be accommodated in the forthcoming years. Non-responses to the survey mean additional capacity is likely to exist. Subsea Infrastructure Removal 98 projects have subsea infrastructure removal requirements based on current potential CoP dates to 223. 88 projects relate to removal of subsea infrastructure up to 4Te, accounting for a cumulative total of 6,395Te and requiring an estimated 1,32 project days to complete. 1 projects relate to removal activities above 4Te, accounting for a cumulative total of 9,19Te and requiring an estimated 21 days to complete. Current capacity far outstrips demand for subsea infrastructure removal, and the backlog of pre-217 activities is not expected to have a significant impact. 5

EXECUTIVE SUMMARY Topside Removal 115 projects were identified with topside removal requirements based on CoP up to 223. The cumulative removal total was 491,335Te requiring an estimated 579 days for removal. Demand for topside removals was estimated to peak between 219 and 22. Current removal capacity is almost double decommissioning demand and the pre-217 backlog of activity is not expected to have a significant impact. Future capacity will be subject to the level of development and decommissioning projects on the UKCS and globally, as well as activities in other sectors such as offshore wind farm construction. Substructure Removal 19 projects were identified with substructure removal requirements based on CoP up to 223. Total substructure tonnage for removal was 294,74Te, requiring an estimated 1,15 vessel days. Demand for substructure removals is likely to peak between 218 and 221. Current capacity exceeds demand for removal of substructures weighing less than 4,Te. Current capacity for substructures over 4,Te appears sufficient to meet current demand. Non-responses to the survey mean vessel availability may in fact be significantly higher. Onshore Decommissioning A total of 81,66Te of infrastructure was estimated for removal from the UKCS, requiring a total of 15,241 days of onshore work Demand for onshore activities is likely to peak in 221 222 and heavily concentrated on assets recovered from the CNS and SNS. 63% of quaysides and 61% of yards have laydown areas which would not be able to accommodate large platforms. Supply and demand for onshore activities were separate aspects due to different data criteria that could not be overlaid. 6 Decommissioning Supply Chain Capacity Report

Conclusions Overall, the research revealed that with current market conditions there appears to be sufficient supply chain capacity to meet the short/medium term demand expected for decommissioning activities on the UKCS. However, this could quickly change should there be a significant upturn in investment across the basin and subject to the extent of utilisation of the UK supply chain by other industries. It can therefore be concluded that the sector currently has a window of opportunity, where unit rates for equipment and services are likely to be lower than historical norms, providing prospects for relatively low-cost decommissioning should mechanisms be found to bring currently deferred work to the market. Given the cyclical nature of the oil and gas sector, it is highly likely that these conditions will not last. Thus, a focus on ensuring that project approval and commencement decisions are made swiftly can be expected to maximise the opportunities to take advantage of such market conditions in future. This will need to include regulatory submission and approval, conceptual and detailed engineering, procurement and contracting, and timely access to capital. Please see Page 33 for a full list of recommendations for improvement to future studies. 7

INTRODUCTION 1 INTRODUCTION The UK oil and gas industry is undergoing a transition, as it strives to adapt to lower oil prices and improve the competitiveness of the United Kingdom Continental Shelf (UKCS), amidst increasing basin maturity. This is critical for securing future developments, maximising economic recovery from existing fields and for decommissioning the infrastructure once production has ceased. With decommissioning activity widely expected to increase over the next ten years the aim is to ensure the supply chain has the necessary capacity to meet decommissioning demand safely and cost efficiently. This report, prepared by Accenture and commissioned by Decom North Sea, Scottish Enterprise and the Oil & Gas Authority, sets out the findings to a study conducted to provide a high-level assessment of the current decommissioning capacity to service UKCS decommissioning demand. It aims to generate greater understanding of supply and demand factors to create visibility and alignment of planning and investment decisions. The Oil & Gas Authority has set a target for the industry of reducing decommissioning costs to 39 billion (a 35% reduction on current estimates).1 Delivering these efficiencies will undeniably present challenges, but importantly, opportunities too. The UK, compared to other oil and gas producing nations, is most advanced in its thinking and leadership around decommissioning. From the regulatory approach, the experience gained, and learning disseminated; these attributes provide the impetus to become a world-leader in decommissioning. Achieving that will require an efficient and effective UK supply chain which is prepared for and flexible to meet decommissioning demand growth in the UKCS and internationally. The study utilised data, provided by the OGA, on projects that had already ceased production or had potential cessation of production (CoP) dates to 223 demand data. A survey questionnaire was issued to relevant companies in the supply chain to determine market availability of critical assets or equipment supply data - to carry out the following six activities: 1. Platform wells plugging and abandonment 2. Subsea wells plugging and abandonment 3. Subsea infrastructure removal 4. Topside removal 5. Substructure removal 6. Onshore remediation, dismantling and recycling. The availability of people, services and secondary equipment supplementing these activities was generally considered to have no current critical constraints, therefore did not form part of the study. The demand and supply data were analysed to assess the extent to which supply capacity would be able to meet the need for forthcoming decommissioning projects (see Appendix for detailed approach). This created a snapshot in time and provided a baseline of current supply capacity in relation to current estimated demand. Figure 1 - Decommissioning Market Levers Guidance Requirements Government/ Regulator Standards Incentives Moderator Decom Supply Chain Operators License to operate Innovation Investments Plans/execution Collaboration - Alliance Innovation Service Capability Demand Market Service Capacity Service Providers Cost-effective offer Innovation Supply Collaboration - Integration (source: OGA, Decom North Sea, Accenture) 1Oil & Gas Authority, UKCS Decommissioning 217 Cost Estimate Report 8 Decommissioning Supply Chain Capacity Report

2 STUDY FINDINGS 2.1 OVERALL UKCS DEMAND Initial analysis of the data provided by the OGA enabled a broad picture of estimated decommissioning requirements to be drawn. From a total of 165 projects, with estimated cessation of production dates up to 223, a breakdown based on UKCS location and activity was discerned. A visual representation of the data is shown in Figure 2. Figure 2 Aggregate UKCS decommissioning demand (based on CoP to 223) SUPPLY AND DEMAND ANALYSIS It is important to note that the demand data shown is indicative, due to largely being based on potential cessation of production (CoP) dates which are subject to market conditions and susceptible to change. 29

STUDY FINDINGS Importantly, only a few projects have firm timescales, and many are still in their early planning stages. The projects also include several with uncompleted activities associated with facilities that ceased production prior to 217. These have been deferred, creating a backlog that will need to be rescheduled in coming years, and which appear in the demand analysis as activities expected in years 213-216. To enable analysis of demand and supply data, the number of days potentially required to carry out each activity was calculated, as shown in Figure 3. Figure 3 Aggregate UKCS decommissioning demand days (based on CoP to 223) Decommissioning Activity Number Demand Days* Platform Wells P&A 84 29,4 Subsea Wells P&A 462 17,7 Subsea Infrastructure Removal <4Te Subsea Infrastructure Removal >4Te 88 1,32 1 21 Topside Removal 115 579 Substructures Removal 19 1,15 Onshore Dismantling (tonnes) 81,66 15,241 * A detailed explanation of the methodology and assumptions employed is provided in the Appendix. The overall demand data was then analysed per decommissioning activity against supply data from the survey questionnaire. 1 Decommissioning Supply Chain Capacity Report

2.2 Platform wells P&A To assess demand for platform wells P&A, the potential demand days for each year was estimated based on potential CoP dates through to 223. To do so, assumptions were made that P&A activities would be carried out in the same year as CoP and that the duration of P&A for each platform well would be 32 days, and for installations with more than 1 wells, 1 in every 1 would require an additional 1 days. The results are shown in Figure 4. The analysis provides a view of likely commencement, volume and duration of P&A activities in each region. Figure 4 UKCS platform wells P&A potential demand days by region (215 223) 1, 9, 8, 7, 6, 5, 4, 3, 2, 1, 215 216 217 218 219 22 221 222 223 SUPPLY AND DEMAND ANALYSIS CNS IS (including EIS) NNS SNS For the 84 platform wells identified, P&A is estimated to require a total of 29,4 days. Importantly, 93% of this demand relates to the CNS and SNS regions, with little activity required in the IS (including EIS) and NNS and none in the WoS. The concentration revealed as many as 77% of platform wells related to just 3% of projects. In the CNS, there are 13 multi-well projects covering a total of 385 wells. Indeed, one CNS project covers as many as 142 wells. In the SNS there are 9 multi-well projects covering 192 wells and in the NNS a single multi-well project covers a total of 42 wells. These multi-well projects provide opportunity to reduce costs by leveraging continuous improvement and forging collaborative projects and innovative commercial arrangements. The data shows a clear peak of overall platform P&A demand in 218. It should be noted that several abandonments, relating to data for 215 217, will need to be rescheduled with the potential impact of pushing P&A activity into later years which may have the effect of creating further peaks in demand. 211

On the supply side, a total of 53 jack-ups and 5 Modular Drilling Units (MDU) were identified as presently able to operate in the UKCS. These figures were derived from the survey, which achieved a response rate of over 6% (see Appendix for details). The potential availability of these assets for each UKCS region is set out in Figure 5. Figure 5 Number of available drilling rigs/units by type and region STUDY FINDINGS Types Total Count Qty that can operate in CNS Qty that can operate in IS (including EIS) Qty that can operate in NNS Qty that can operate in SNS Jack-up 53 31 53 53 MDU 5 5 5 5 5 Total Vessels 58 A key issue identified concerned availability of jack-ups, which was assessed based on the water depth each asset could operate in. This led to the conclusion that jack-ups are generally not suitable for NNS operations, meaning this region would be dependent on MDUs. However, rig availability would be dependent on a broader set of factors including geographical area, operational constraints, services provided by the asset, platform configuration and project specifics. To assess the supply chain s current capacity to meet likely future demand, the survey results were used to calculate the maximum number of potential available days for each asset type over 217/18. This resulted in 6,761 days for Jack-up rigs and 931 days for MDUs. It should be noted that this represents maximum capacity and does not account for work conducted simultaneously in multiple regions, or for potential increases in demand elsewhere such as exploration and production drilling. This snapshot of current availability was compared against potential demand. The results for the whole of the UKCS are shown in Figure 6. Figure 6 UKCS platform wells P&A demand vs supply (215 223) 1, 9, Potential Total Demand Potential Maximum Supply (217-218) 8, 7, 6, 5, 4, 3, 2, 1, 6,761 931 215 216 217 218 219 22 221 222 223 Jack-up MDU 12 Decommissioning Supply Chain Capacity Report

Figure 6 shows that, in general, available supply throughout 217/18 outstrips likely demand in every year except 218. However, the backlog of activities from pre-217 is likely to alter demand in subsequent years. At a regional level, the picture is much the same. In regions like the IS (including EIS) and the SNS, there appears to be sufficient capacity to meet current potential platform wells P&A demand, including in 218. The only immediate area of concern is the CNS, where demand appears to outstrip available supply in 218 (see Figure 7). The CNS may experience capacity constraints in 218 given this likely demand for platform wells P&A. Figure 7 CNS platform wells P&A demand vs supply (215 223) 6, 5, 4, 3, 2, 1, Potential CNS Demand Potential Supply (217-218) 3,775 931 STUDY FINDINGS 215 216 217 218 219 22 221 222 223 Jack-up MDU The analysis however did not account for P&A that could be undertaken using existing platform-based drilling rigs (PBDR). There are examples of PBDR being refurbished to carry out P&A, however, maintenance and refurbishment can be costly and possibly prohibitive. It is recommended that future studies incorporate this parameter. Summary For platform wells P&A activity across the whole of the UKCS, there appears to be more than enough current capacity to meet likely future demand. However, areas of concern were identified in two regions: the CNS and NNS. Key observations and recommendations 84 platform wells will require P&A based on current potential CoP dates to 223 Overall there appears to be sufficient capacity in 217/18 to meet this potential demand If activity proceeds as estimated the CNS may experience capacity constraints in 218 The NNS region is likely to be reliant on MDUs for P&A activity due to water depth constraints associated with jack ups Platform-Based Drilling Rigs (PBDRs) may be reactivated to carry out platform well P&A and would help to mitigate capacity constraints. This parameter did not form part of the analysis and is recommended for inclusion in future studies. 213

2.3 Subsea wells P&A To assess demand for subsea wells P&A, the potential demand days for each year was estimated based on potential CoP dates through to 223. The assumptions made were that P&A activities would be carried out four years after CoP, except for the SNS where it was assumed activity would take place after two years. SUPPLY AND DEMAND ANALYSIS The duration of P&A for each subsea well was estimated as 32 days, and for fields with more than 1 wells, 1 in every 1 would require an additional 1 days. The results are shown in Figure 8. The analysis provides a view of likely commencement, volume and duration of P&A activities in each region. It should be noted that a small number of subsea abandonments relating to 211 217 will need to be rescheduled which will marginally alter subsequent demand. Figure 8 UKCS subsea wells P&A potential demand days by region (215 227) Potential Total No of Days by Region 4,5 4, 3,5 3, 2,5 2, 1,5 1, 5 215 216 217 218 219 22 221 222 CNS NNS SNS WoS 223 224 225 226 227 For the 462 subsea wells identified, P&A was estimated to require a total of 17,7 days. Figure 8 shows subsea well P&A activity increasing over the coming years, potentially peaking around 224. Demand is concentrated in the CNS and NNS regions, representing 81%. The remaining activity is equally split between the SNS and WoS and none expected in the IS (including the EIS). Nearly half (43%) of subsea wells relate to just 9% of projects. In the CNS there are 6 multi-well projects covering 114 wells. The NNS has 3 projects covering 37 wells and the WoS region has a single project covering 46 wells. These multi-well projects provide opportunity to reduce costs by entering into collaborative ventures, innovative commercial arrangements, and leveraging continuous improvement. On the supply side, a total of 118 vessels/rigs were identified with current capacity to undertake subsea wells P&A in the UKCS. This figure was derived from the survey, to which nearly two thirds responded (54 from a total of 86 companies contacted). The potential availability of these assets in each region is set out in Figure 9. It should be noted that availability was assessed based on the water depth each could operate in but this is likely to be dependent on a broader set of factors including geographical area, operational constraints, services provided by the asset, platform configuration and project specifics. 14 Decommissioning Supply Chain Capacity Report

Figure 9 Number of available vessels/rigs by type and region Types Total Count Qty that can operate in CNS Qty that can operate in NNS Qty that can operate in SNS Qty that can operate in WoS LWIV 7 7 7 7 7 Jack-up 6 41 1 6 18 Semi-sub 44 44 44 38 44 Supply Vessel (with Modular Spread) Total Vessels 118 7 7 7 7 7 STUDY FINDINGS Based on this availability, and to assess current capacity to meet likely future demand, the results were used to calculate the maximum number of potential available days over 217/18, for each asset type by region. This resulted in total availability of 1,38 days for LWIVs, 7,69 days for Jack-up rigs, 5,697 days for Semi-Subs and 1,33 days for Supply Vessels with Modular Spreads. A snapshot of this availability compared against potential demand for the whole of the UKCS is shown in Figure 1. This shows that current supply appears to clearly outstrip projected annual demand. This does however represent maximum capacity and does not account for work conducted simultaneously in multiple regions, or for potential increases in demand elsewhere such as exploration and production drilling or other marine sectors. Figure 1 UKCS subsea wells P&A demand vs supply (215-227) Potential Supply Vs Demand (Total) Potential Total Demand 8, 7, Potential Maximum Supply (217 218) 7,69 6, 5, 4, 3, 2, 1, 1,38 5,697 1,33 215 216 217 218 219 22 221 222 223 224 225 226 227 LWIV Semi-sub Supply Vessel Jack-up The results for the CNS, NNS, WoS and SNS regions are set out in Figures 11 to 14. Demand in the CNS and NNS begins to 2 grow from 219 onwards although this appears to be variable. This may be smoothed significantly as project schedules are developed. Current availability does appear to be sufficient, but there may be limited capacity to undertake rig-less activity (with LWIVs and Supply Vessels with Modular Spreads) if well complexities permit this approach. Demand in the WoS and SNS regions (Figures 13 and 14) are expected to be limited. 15

Potential Supply Vs Demand (CNS) Figure 11 CNS subsea wells P&A demand vs supply (215-227) Potential CNS Demand 6, Potential Supply (217-218) 5,697 5,561 5, STUDY FINDINGS 4, 3, 2, 1, 215 216 217 218 219 22 221 222 223 224 225 226 227 1,38 1,33 LWIV Semi-sub Supply Vessel Jack-up Figure 12 NNS subsea wells P&A demand vs supply (215-227) Potential Supply Vs Demand (NNS) 6, Potential NNS Demand Potential Supply (217 218) 5,697 5, 4, 3, 2, 1, 1,38 1,33 1,829 215 216 217 218 219 22 221 222 223 224 225 226 227 LWIV Semi-sub Supply Vessel Jack-up Figure 13 WoS subsea wells P&A demand vs supply (215-227) 6, Potential WoS Demand Potential Supply (217-218) 5,697 5, 4, 3, 2, 1, 1,38 1,33 2,552 215 216 217 218 219 22 221 222 223 224 225 226 227 LWIV Semi-sub Supply Vessel Jack-up 16 Decommissioning Supply Chain Capacity Report

Figure 14 SNS subsea wells P&A demand vs supply (215-224) Potential Supply Vs Demand (SNS) Potential SNS Demand 8, Potential Supply (217 218) 7,69 7, 6, 5, 4, 3, 2, 1, 215 216 217 218 219 22 221 222 223 224 464 4,781 1,33 LWIV Semi-sub Supply Vessel Jack-up STUDY FINDINGS For subsea wells P&A, there appears to be sufficient capacity at present to meet current projected decommissioning demand. It also appears that the backlog of activities dating from before 217 could easily be accommodated in the forthcoming years. The survey was subject to non-responses, therefore additional capacity is likely to exist. Moreover, evolving macroeconomic and market conditions are likely to alter, and potentially reduce capacity for subsea wells P&A. Rigs or vessels may secure work associated with exploration and production activity or overseas. Equally older assets may be taken out of service and stacked and new capacity may enter the market. There is therefore currently an economic window of opportunity, but significant capacity could be moved from the basin or scrapped if not utilized which would place upward pressure on availability and costs. Key observations and recommendations 462 subsea wells will require P&A based on current potential CoP dates to 223 Despite this demand, subsea wells P&A current supply clearly exceeds potential demand, and the backlog of pre-217 activities could easily be accommodated in the forthcoming years. Non-responses mean additional capacity is likely to exist. This factor should be considered, and appropriate treatment incorporated in future studies. 217

2.4 Subsea infrastructure removal SUPPLY AND DEMAND ANALYSIS A total of 98 projects were identified with subsea infrastructure removal requirements. To assess demand for subsea infrastructure removal, the potential demand days for each year was estimated based on potential CoP dates through to 223. The assumptions made were that removal activity would take place four years after CoP, except for in the SNS where this was assumed to be two years after CoP. The duration of subsea removal activities was estimated based on the tonnage to be removed. Figure 15 shows the number of removal days to be utilised associated with subsea infrastructure, ranging from 15 days for projects with less than 5 tonnes of recovered material to a maximum of 4 days for more than 2,1 tonnes. Figure 15 Subsea infrastructure removal days by weight (Te) Subsea Tonnage - 5 51-1, 1,1-2, >2,1 Removal Days 15 2 3 4 In parallel, the analysis of supply capacity has defined vessel suitability based on a 4Te vessel capability, as this best reflects the boundary point between vessel types with differing capabilities for these activities. The results are shown in Figures 16 and 17. This gives a picture of the likely commencement, volume and duration of subsea infrastructure removal activities in each region (note that the data only accounts for actual removal operations, not preparatory work). Both graphs show demand for subsea infrastructure removal peaking between 219 and 224. Figure 16 represents 88 projects with associated subsea infrastructure removal up to 4Te. Cumulatively this accounts for 6,395Te, requiring an estimated 1,32 project days to complete. Initial demand is concentrated in the SNS region, with a shift to a focus on the CNS region from 221 onwards. The NNS and particularly the WoS area make minor contributions to the demand. A crucial point to note is that 61% of these removal projects are below 1Te. Consequently, actual demand days may be significantly more than forecast due to the potential for inefficiencies associated with small individual projects and a greater number of mobilisation/demobilisation activities. These projects would ideally be candidates for multi-operator/ multi-project decommissioning campaigns to deliver more cost-effective activities. 18 Decommissioning Supply Chain Capacity Report

Figure 16 UKCS subsea infrastructure removal potential demand days by region (up to 4Te) 3 25 2 15 1 5 211 213 217 218 219 22 221 222 CNS NNS SNS WoS 223 224 225 226 227 STUDY FINDINGS Figure 17 represents 1 projects with associated subsea infrastructure removal over 4Te, accounting for cumulative removal of 9,19Te with an estimated 21 days to complete. Figure 17 UKCS subsea infrastructure removal potential demand days by region (above 4Te) 7 6 5 4 3 2 1 219 22 221 222 223 224 225 226 CNS NNS SNS WoS On the supply side, data was received from approximately 6% of companies surveyed (49 out of 78 contacted). A total of 36 vessels were identified as available for activities on subsea infrastructure up to 4Te and eight Heavy Lift Vessels (HLV) for infrastructure above 4Te. The assessment was made according to the water depth each vessel could operate in. However, it is important to note that other variables can impact this availability (operational constraints, geographical area, services provided by the vessel, project specifics) which have not been considered in this analysis. The availability breakdown for each region and activity is shown in Figures 18 and 19. 219

Figure 18 Number of available vessels by subsea infrastructure type and region (up to 4Te) STUDY FINDINGS Types Total Available Vessels Removal of Pipelines Removal of Subsea Structures (manifolds, WHPS, concrete bases) Removal of Pipeline Stabilisation aids (mattresses) CNS 31 19 24 18 NNS 3 19 23 18 SNS 36 2 28 21 WoS 3 19 23 18 Figure 19 Number of available HLV by subsea infrastructure type and region (above 4Te) Types Total Available Vessels Removal of Pipelines Removal of Subsea Structures (manifolds, WHPS, concrete bases) Removal of Pipeline Stabilisation aids (mattresses) CNS 6 6 6 4 NNS 5 5 5 3 SNS 8 8 8 5 WoS 6 6 6 4 To assess current capacity to meet future demand, the survey results were used to calculate the maximum number of potential available days for each vessel type per region ( available vessel days see Appendix for calculation). This snapshot of current availability was compared against potential demand. While demand over the coming years was estimated at 1,32 days for projects up to 4Te) and 21 days for projects above 4Te, available supply for 217/18 was estimated to be 1,571 days for CSVs; 796 days for DSVs; 1,58 days for MSVs; 1,43 days for ROVSVs and 716 days for HLVs. The snapshot of current availability compared against potential demand for the CNS, NNS, SNS and WoS regions are set out in Figures 2 to 26. In general, there appears to be far more capacity than is required to meet current demand for subsea infrastructure removal (both for infrastructure up to 4Te and for infrastructure above 4Te). Moreover, any backlog of pre-217 activities is not expected to have a significant impact. However, it should be noted that this represents maximum capacity and does not account for work conducted simultaneously in multiple regions, or for potential increases in demand elsewhere globally. 2 Decommissioning Supply Chain Capacity Report

Figure 2 CNS subsea infrastructure demand vs supply (up to 4Te) 1,6 1,4 Potential CNS Demand up to 4Te 1,571 Potential Supply (217-218) 1,2 1, 8 6 4 2 217 218 219 22 221 222 223 224 225 226 227 1,43 745 689 CSV DSV MSV ROVSV STUDY FINDINGS Figure 21 CNS subsea infrastructure demand vs supply (above 4Te) 6 5 4 3 2 1 Potential CNS Demand above 4Te Potential Supply (217-218) 54 217 218 219 22 221 222 223 224 225 226 227 HLV In the CNS region, demand appears to peak in the period 221 224 with a mix of both small (<4Te) and larger projects. Suitable vessel supply capacity appears to be good for all categories of vessel. Figure 22 NNS subsea infrastructure demand vs supply (up to 4Te) 1,6 1,4 Potential NNS Demand up to 4Te 1,571 Potential Supply (217-218) 1,2 1, 8 6 4 745 643 1,43 2 217 218 219 22 221 222 223 224 225 226 227 CSV DSV MSV ROVSV 221

Figure 23 NNS subsea infrastructure demand vs supply (above 4Te) STUDY FINDINGS 45 4 35 3 25 2 15 1 5 217 218 Potential NNS Demand above 4Te 219 22 221 222 223 224 225 226 227 Potential Supply (217-218) In the NNS region, demand appears to be limited with activity spread unevenly across the period from 219-227 with large projects not expected to occur before 225. Suitable vessel supply capacity appears to be good for all categories of vessel. 411 HLV Potential Supply Vs Demand (SNS) up to 4 Te Figures 24 SNS subsea infrastructure demand vs supply (up to 4Te) 1,6 1,4 Potential SNS Demand up to 4Te 1,571 Potential Supply (217 218) 1,2 1, 8 6 4 796 1,58 1,43 2 211 212 213 214 215 216 217 218 219 22 221 222 223 224 225 CSV DSV MSV ROVSV Figures 25 SNS subsea infrastructure demand vs supply (above 4Te) 8 7 Potential SNS Demand above 4Te Potential Supply (217-218) 716 6 5 4 3 2 1 217 218 219 22 221 222 223 224 225 HLV 22 Decommissioning Supply Chain Capacity Report

In the SNS region, demand appears to be grow rapidly from 217 until declining significantly after 22. The majority of projects are small (<4Te) and suitable vessel supply capacity appears to be good for all categories of vessel. Figure 26 WoS subsea infrastructure demand vs supply (up to 4Te) Potential Supply Vs Demand (WoS) up to 4 Te 1,6 1,4 1,2 1, 8 6 4 2 217 218 219 Potential WoS Demand up to 4Te 22 221 222 223 224 225 226 227 Potential Supply (217-218) 1,571 1,43 745 643 CSV DSV MSV ROVSV STUDY FINDINGS WoS activity is limited to a single small (<4Te) project in 224 and suitable vessel supply capacity appears to be good for all categories of vessel. Summary Current capacity was found to exceed current decommissioning demand for subsea infrastructure removal both up to and above 4Te. The backlog of pre-217 activities is not expected to have a significant impact. Furthermore, a large surplus in capacity is likely to affect contractor ability to maintain investment, representing a risk to the supply chain s ability to meet future decommissioning demand. Evolving macroeconomic and market conditions are also likely to alter capacity. A favourable shift may see assets deployed in non-decommissioning projects or overseas. Alternatively, assets may even be sold. There is therefore a current window of opportunity with over-capacity and an opportunity for activities to be executed cost-effectively. Key observations and recommendations 98 projects have subsea infrastructure removal requirements based on current potential CoP dates to 223. 88 projects relate to removal of subsea infrastructure up to 4Te, accounting for a cumulative total of 6,395Te and requiring an estimated 1,32 project days to complete. 1 projects relate to removal activities above 4Te, accounting for a cumulative total of 9,19Te and requiring an estimated 21 days to complete. Current capacity far outstrips demand for subsea infrastructure removal, and the backlog of pre-217 activities is not expected to have a significant impact. 223

2.5 Topside removal SUPPLY AND DEMAND ANALYSIS To assess demand for topside infrastructure removal, the potential demand days for each year was estimated based on potential CoP dates through to 223. The assumptions made were that topside removal activity would take place two years after CoP, except for in the SNS where this was assumed to be one year after CoP. The duration of topside removal activities for each region was estimated based on vessel days per tonnage range, shown in Figure 27. Figure 27 Topside removal vessel days (per tonnage range) by region Topside Tonnage 1,6 1,61-4, 4,1-8, 8,1-16, >16, CNS, NNS 1.25 3.75 6.25 12.5 27.5 IS (including EIS), SNS 1.25 3.75 5 - - In total, 115 projects were identified with topsides removal requirements between 213 and 225, comprising a total tonnage of 491,335Te and requiring an estimated 579 vessel days for removal (note this considers actual removal operations, not preparatory work). Figure 28 demonstrates most of these projects are concentrated in the CNS and SNS regions, which account for 94% of all projects. There are no topsides to be removed in the WoS region. The graph shows that demand for topside removals is likely to peak between 219 and 22. Projects associated with activity dates prior to 217 are caused by a current backload of unexecuted work relating to facilities with CoP dates prior to 217. Figure 28 UKCS topside removal potential demand days by region (213 225) Potential Topside Demand Days, by Region 14 12 1 8 6 4 2 213 214 215 216 217 218 219 22 221 222 223 224 225 CNS IS (including EIS) NNS SNS On the supply side, validated survey data was received from 57% of companies contacted with vessels potentially suitable to undertake topsides removal. Fourteen Heavy Lift Vessels (HLVs) were identified as currently available to perform decommissioning work. To assess current capacity to meet future demand, the survey results were used to calculate the maximum number of potential available days for each HLV per region ( available vessel days see Appendix for calculation). The results are shown in Figure 29 together with the number of available HLVs per region. 24 Decommissioning Supply Chain Capacity Report

Figure 29 Number of available Heavy Lift Vessels by region Types Total Count Qty that can operate in CNS Qty that can operate in IS (including EIS) Qty that can operate in NNS Qty that can operate in SNS HLV 14 11 14 8 14 Number of Days Available by Region This snapshot of current availability was compared against potential demand, shown in Figure 3. Figure 3 UKCS topsides removal demand vs supply (213-227) Potential Total Max Supply Vs Demand 1,2 1, 8 6 4 2-1,81 1,142 699 1,142 Potential Total Demand Potential Maximum Supply (217-218) 1,142 STUDY FINDINGS 213 214 215 216 217 218 219 22 221 222 223 224 225 226 227 HLV Based on the total 579 estimated demand days, the total available capacity was almost double, revealing significant available excess supply. Any backlog from pre-217 activities is not expected to have a significant impact. Analysis at the regional level revealed similar results. Summary For topside removal activities on the UKCS utilising HLV, analysis reveals there is presently excess capacity to meet decommissioning demand. HLVs are however highly mobile, therefore future capacity will be determined by the level of development and decommissioning projects both on the UKCS and globally, as well as activities in offshore renewables projects. Key observations 115 projects were identified with topside removal requirements based on CoP up to 223. The cumulative removal total was 491,335Te requiring an estimated 579 days for removal (not including time for preparatory work). Current removal capacity is almost double decommissioning demand and the pre-217 backlog of activity is not expected to have a significant impact. Future capacity will be subject to level of development and decommissioning projects on UKCS and globally, as well as activities in other sectors such as offshore wind farm construction. 225

2.6 Substructure removal SUPPLY AND DEMAND ANALYSIS To assess demand for substructure removal, the potential demand days for each year was estimated based on potential project CoP dates up to 223. The assumptions made were that substructure removal activity would take place three years after CoP, except in the SNS where this was assumed to be one year after CoP. The duration of substructure removal activities for each region was then estimated based on vessels days per tonnage range shown in Figure 31. Figure 31 Substructure removal vessel days (per tonnage range) by region Substructure Tonnage 1,6 1,61-4, 4,1-8, 8,1-16, >16, CNS 7 7 7 27 4 NNS - - 7 27 4 IS (including EIS) 7 7 7 27 - SNS 7 7 7 - - In total, 19 projects were identified with substructure removal requirements between 214 and 226, comprising a total tonnage of 294,74Te and requiring an estimated 1,15 vessel days for removal. Figure 32 demonstrates most of these projects are concentrated in the CNS and SNS regions, which account for 94% of substructures to be removed. The graph shows that demand for substructure removal is likely to peak between 218 and 221. The analysis revealed that 74% of substructures for removal weigh less than or equal to 1,6Te and 5% are below 1,Te, particularly those in the SNS. Of those remaining, 15 weigh more than 8,Te and 4 are heavier than 16,Te. Figure 32 UKCS substructure removal potential demand days by region (214 226) 25 2 15 1 5 214 215 216 217 218 219 22 221 222 223 224 225 226 CNS IS (including EIS) NNS SNS On the supply side, substructures are generally removed by Heavy Lift Vessel (HLV) with support from other vessels/ barges. The survey data identified 15 HLVs with current availability for substructure removal. This was based on a response rate of 57% (51 of 9 companies contacted). These figures will therefore not represent total available capacity. The regions in which HLVs could operate was assessed in accordance with water depth. The breakdown of available HLVs based on these criteria is shown in Figure 33. It was recognised that other potential operational constraints would exist such as substructure configuration, but additional factors were not considered for this study. 26 Decommissioning Supply Chain Capacity Report

Figure 33 Number of available Heavy Lift Vessels (Te) Types Total Count Up to 1,6 1,61-4, 4, - 8, >16, HLV 15 7 6 1 1 To assess current capacity to meet future demand, the survey results were used to calculate the maximum number of potential available days for HLVs in each region. The analysis was segmented into three groups: substructures up to 1,6Te, substructures between 1,6Te and 4,Te, and substructures above 4,Te. This snapshot of current availability was compared against potential demand. The results are shown in Figures 34 to 36. The graphs show there is currently far more capacity overall than is required to meet decommissioning demand for substructures less than 1,6Te and up to 4,Te. Moreover, there is no significant backlog of pre-217 activities which might affect this capacity. However, there is potential for a bottleneck of availability to handle the larger structures, given that some of the limited number of suitable HLVs may be employed in other sectors. Figure 34 UKCS substructure removal demand vs supply (up to 1,6Te) STUDY FINDINGS 6 Potential Demand (up to 1,6Te) Potential Maximum Supply (217-218) 61 5 4 3 2 1 214 215 2 9 216 217 46 218 9 15 6 3 3 8 219 22 221 222 223 224 225 226 Maximum Supply CNS SNS In Figure 34 projects are predominantly in the SNS region with activity forecast to peak in 218 and continue until 224. Potential supply appears to be more than sufficient for the projected workload. Figure 35 UKCS substructure removal demand vs supply (1,6Te - 4,Te) Potential Demand (1,6-4,Te) Potential Maximum Supply (217-218) 6 61 5 4 3 2 1 9 18 214 215 216 217 218 4 1 1 9 1 219 22 221 222 223 224 CNS SNS 225 226 Maximum Supply 227

Figure 36 UKCS substructure removal demand vs supply (over 4,Te) 5 45 Potential Demand (over 4,Te) Potential Maximum Supply (217-218) STUDY FINDINGS 4 35 3 25 2 15 1 5 214 215 216 217 218 17 219 74 22 39 221 19 222 3 22 3 223 224 225 13 226 93 Maximum Supply CNS SNS NNS In Figure 36, projects are predominantly in the CNS region with activity forecast to peak in 22 and continue until 226. Potential supply appears to be sufficient for the projected workload if demand can be smoothed over several years. Sufficient capacity will also be sensitive to potential utilisation in other sectors, regions and projects with smaller lifts. Summary Overall, there appears to be adequate capacity for substructure removal activities on the UKCS at present. However, several relevant companies did not respond to the supply survey, suggesting vessel availability may in fact be significantly higher. Key observations 19 projects were identified with substructure removal requirements based on CoP up to 223. Total substructure tonnage for removal was 294,74Te, requiring an estimated 1,15 vessel days. Demand for substructure removals is likely to peak between 218 and 221 Current capacity exceeds demand for removal of substructures weighing less than 4,Te Current capacity for substructures over 4,Te appears sufficient to meet current demand 28 Decommissioning Supply Chain Capacity Report

2.7 Onshore remediation, dismantling and recycling The onshore element of decommissioning did not compare supply and demand data. This was due to the data for each having different criteria that could not be overlaid. The two elements are therefore presented separately. Demand To assess demand for onshore decommissioning activities, the potential demand days for each year was estimated based on potential CoP dates up to 223. The assumptions made were that onshore activity would take place four years after CoP, except for in the SNS where this was assumed to be one year after CoP. The duration of onshore decommissioning was also estimated based on the type of infrastructure and tonnage using the scale shown in Figure 37. Figure 37 Onshore decommissioning duration by infrastructure type and weight Activity Te Ranges Days Subsea Infrastructures 2, 14 Substructures 1, - 1,5 28 Topsides 2, - 3, 28 The results are shown in Figure 38. In total, 81,66Te of UKCS infrastructure is estimated to require a total of 15,241 days of onshore decommissioning. As much as two-thirds (534,Te) is concentrated in assets to be recovered from the CNS. The graph shows activity is likely to peak in 221 and 222. SUPPLY AND DEMAND ANALYSIS Figure 38 UKCS onshore decommissioning potential demand days by region (215-227) 4, 3,5 3, 2,5 2, 1,5 1, 5 215 216 217 218 219 22 221 222 223 224 225 226 227 CNS IS (including EIS) NNS SNS WoS 2 29

Supply Ports and onshore yards were surveyed to determine the number of facilities, with relevant permits/certifications, able to process offshore infrastructure. From the 85 companies contacted, 4 responded. STUDY FINDINGS For the purposes of this survey, a port was defined in terms of having a quayside including berth, lay-down area and any adjacent working area. A yard was defined as a piece of uncultivated ground either adjacent to quayside or standalone out with port grounds. It is understood that a potential bottleneck could arise if ports and yards lack dismantling contractors with the necessary permits / licenses to undertake the work onshore, such as Pollution Prevention and Control permits (PPCs), Radioactive Substances Authorisations (RSAs), Waste Management Licences (WMLs) and Controlled Activities Regulations Licenses (CARs). Respondents were asked to indicate the status of their permits / licenses, results of which show that a range of sites across the UK are available to perform decommissioning work. Scotland has 33 sites with a total of 69 permits, East England has 3 sites with 7 permits, North East England has 13 sites with 31 permits, and Northern Ireland has 5 sites with 15 permits. Note: 19% of sites surveyed did not specify whether they have permits to operate. The survey also revealed that most sites (63% of quaysides and 61% of yards) have laydown areas less than 25,sqm. These sites may therefore be more suited to smaller structures and not large complete topsides, unless removed in modules / or piece small activity. The geographic distribution of sites with sufficient available laydown area to accept large structures is shown in Figure 39. Only 12 sites provided information on the bunded area available for contaminated materials - all located on the east coast. It was therefore not possible to determine west coast capacity which may be preferable for decommissioning assets removed from the IS (including the EIS). 3 Decommissioning Supply Chain Capacity Report

Figure 39 Regional location of sites with >25,sqm available laydown area sufficient for larger structures Northern Ireland 17,85 283,m 2 Scotland 134 45,m 2 NE England 44 63,m 2 44 63,m 2 STUDY FINDINGS NW England 1,m 441 1 1,m 2 63,m 2 2 SE England 2 8,m 2 Summary The onshore element of decommissioning presented supply and demand for onshore activities separately due to different data criteria that could not be overlaid. The size of the quayside/yard, the extent of permits in place, the presence of nearby infrastructure, and the availability of skilled personnel onsite, can all have a major impact on a region s decommissioning capacity. Key observations A total of 81,66Te of infrastructure estimated to be removed from the UKCS, requiring a total of 15,241 days of onshore work. Demand for onshore activities is likely to peak in 221 222 and heavily concentrated on assets recovered from the CNS and SNS. 63% of quaysides and 61% of yards have laydown areas less than 25,sqm thereby unable to accommodate large platforms. 231

3 CONCLUSIONS Overall, in 217/18 there appears to be sufficient, and at times surplus, available capacity of key assets to meet potential UKCS decommissioning demand, but this could rapidly change. CONCLUSIONS The analysis is based on a snapshot of a market in a downturn and an industry undergoing meaningful change. There are many uncertainties surrounding UKCS decommissioning that make projects coming to fruition and therefore assessing future capacity at the industry level a challenge. Potential capacity constraints were identified for platform wells P&A in the Central North Sea in 218 and a potential reliance in the Northern North Sea on Modular Drilling Units. However, Platform-Based Drilling Rigs may be reactivated and would help to mitigate capacity constraints. Excess capacity was found in relation to demand for subsea infrastructure removal both up to and above 4Te. A large surplus in capacity is likely to affect contractor ability to maintain investment and the integrity and operability of their assets. This could result in re-deployment overseas or stacking or even sale for decommissioning. This presents a risk to meeting future decommissioning demand, particularly if activity and capacity requirements increase in exploration and production and other marine sectors. Similarly, topside and substructure removal was found to have excess capacity in Heavy Lift Vessel (HLV) utilisation. These assets are also highly mobile, therefore future capacity will be determined by the level of new development and decommissioning projects both on the UKCS and globally, as well as activities in offshore renewables projects. The onshore element of decommissioning presented supply and demand for onshore activities separately due to different data criteria that could not be overlaid. The size of quaysides and yards, the permits in place, presence of nearby infrastructure, and availability of skilled personnel onsite, can all have a major impact on a region s decommissioning capacity. Oil and gas companies are operating in an environment today that bears little resemblance to that of just a few years ago. The industry is subject to evolving macroeconomic and market conditions and has been (and will continue to be) shaken and disrupted by forces that go far beyond supply and demand. These external forces may have a significant impact on UKCS decommissioning capacity: Oil price fluctuations The industry is currently adapting to lower oil prices. Should the oil price rebound, and efficiency improvements continue, some late-life fields currently not considered economically viable may become so, pushing decommissioning activities further into the future. A high oil price could also prompt investment to develop new fields, which, in turn, could lead to the supply chain diverting its available capacity towards those projects. Regulatory framework The recent introduction of transferable tax credits2 between buyers and sellers of North Sea assets has the potential to extend economic recovery in the North Sea. This could impact current estimated Cessation of Production dates within the demand profile. Increasing competition for the UK supply chain Offshore wind developments are expected to increase over the next 5 years. This market draws on much of the fleet/equipment and workforce identified in this study. Together with potential increases in exploration and production activity, competition for what is essentially the same supply chain capacity could significantly alter the supply demand dynamics analysed in this report. New decommissioning-centric technologies and processes The technologies and processes leveraged today were not necessarily designed or built with decommissioning in mind. New potential will emerge, for example, the ability to shift from reverse installation to single lift removal (enabled by the Pioneering Spirit). This means that processes and critically underpinning technologies, are likely to develop further and become more decommissioning-centric. The duration and cost of decommissioning will thus be further optimised, with the potential to radically alter existing baselines/estimates for decommissioning projects. This report offers a comparison of current capacity and expected demand. However, this will change over time as project schedules change and assets are added to or removed from the supply chain. 2UK Government - An outline of the transferable tax history mechanism for UK oil producers that will apply to deals that complete on or after 1 November 218. https://www.gov.uk /government /publications/anoutline-of-transferrable-tax-history 32 Decommissioning Supply Chain Capacity Report

4 RECOMMENDATIONS FOR FUTURE STUDIES To improve future studies, the following observations and recommendations have been made: It is recommended this study be completed on an annual basis to create transparency and capture emerging trends of supply in relation to demand to ensure sufficient capacity is available (or made available) for decommissioning activities. The survey represents a good proportion of companies with key assets currently available for decommissioning activity in the UKCS. The research was undertaken during May to September 217, therefore impacted by the summer holiday period. Future surveys should be performed out with holiday periods and should seek to increase the number of companies participating to ensure solid representation and increasing accuracy of annual supply and demand trends. Many respondents exited the survey at the point at which detailed information regarding their assets/ vessels was being sought. This may have been because data was not readily available. Future studies should seek to simplify response requirements and provide information in advance on data to be collected, to increase both quantity and quality of responses. The assumptions this study was based on should be further validated and/or improved based on industry feedback. Limited data was available on abandonment methods and capacity for platform wells P&A. The use of platform rigs or modular units could not be quantified. Future studies should seek to incorporate this information. It was not possible to analyse supply and demand for onshore activity due to non-availability of matching data. Future studies should seek to collect data that can be better aligned for analysis. RECOMMENDATIONS FOR FUTURE STUDIES 433

Project methodology and approach APPENDIX The primary objective of this project was to understand the capacity of the decommissioning supply chain to fulfil UK/UKCS decommissioning demand in the forthcoming years. The analysis to support this central question was performed by breaking it into two parts: the market supply side (that is, potential capacity available in the supply chain/market today to serve UKCS decommissioning demand) and the market demand side (that is, demand for decommissioning services expected in the years to come). The rationale for this approach was that by understanding the current picture of available capacity in the supply chain and comparing it with the future demand for decommissioning services, insights into potential bottlenecks or oversupply could be gained. Market supply data To establish a view of supply, a survey of relevant supply chain companies was undertaken to determine capacity in key activities. The response rate to the survey is shown below. Figure A1 - Number of Companies in UK Decommissioning Supply Chain Survey by Activity Area Number of Companies Activity Area Contacted for the Survey Responded to the Survey Platform Wells 86 54 Subsea Wells 86 54 Topsides 9 51 Substructure 9 51 Subsea Infrastructure 78 49 Yards 85 4 Ports 85 4 34 Decommissioning Supply Chain Capacity Report

To finalise the scope of the survey and the questionnaire to be used, Accenture facilitated a survey workshop with the Project Work Group (comprising Decom North Sea, SE and the OGA) and 21 industry experts. The workshop participant list was finalised by the PWG with the aim of ensuring that subject matter experts from companies representing specialist areas within decommissioning were involved. Accenture thereafter proposed the target audience for the survey. The PWG reviewed the participant list and identified any additional companies. The survey was targeted at supply chain members owning major assets/vessels which today serve decommissioning projects. Supply chain members owning other services and activities, such as people services, secondary equipment and project management services which supplement the major assets/vessels were not targeted as part of the survey. This was because it was generally understood that these would be available (or made available) on demand and would not necessarily be cause for capacity concern. The survey questionnaire was designed to gather a view of the current major assets/vessels in the market which can service UK/UKCS decommissioning demand. Additionally, the survey established from respondents the potential annual availability of these major assets/vessels (in days) over the course of a typical year. However, it was understood that there would be numerous factors (like maintenance, transit to field, time contracted with non-ukcs demand etc.) which would potentially limit this availability. To account for this, a duration factor was applied to all available capacity data gathered from the survey. This was calculated as shown below: Available vessel days collated via survey responses (A) Total vessel duration days annually (B) = 16 days o 45 days vessel mobilisation/transit sailing annually, plus o 15 days vessel maintenance days annually, plus o 1 days serving non-uk decommissioning projects - greenfield /brownfield annually. Net available vessel days to be compared to potential decommissioning demand (C) A B = C Applying the above, provided the net available vessel days. 35

Market demand data Demand data was provided by the Oil & Gas Authority (OGA). The data numbered 165 projects and their associated or potential year of Cessation of Production (CoP) which ranged from 211-223. The number of platform and/or subsea wells per project and associated tonnage for subsea, topside and jacket infrastructure was also given. APPENDIX Assumptions were then made by the Project Work Group and industry experts on when key activities were likely to be executed. The table below shows the offset determined, which was based on year of actual or potential CoP plus number of years to P&A or removal. Figure A2 - Table Showing Offset in Execution for Key Decommissioning Activities (CoP + X Years) Region Platform well P&A Subsea well P&A Topside Removal Substructure Removal Onshore Disposal (Start) Subsea Infrastructure Removal NNS 4 2 3 4 4 CNS 4 2 3 4 4 SNS 2 1 1 1 2 WoS 4 2 3 4 4 IS (including EIS) 4 2 3 4 4 The demand days for each of the six key activity areas were calculated as follows: 1. Platform Wells - P&A for each platform well would be 32 days, and for installations with more than 1 wells, 1 in every 1 would require an additional 1 days. 2. Subsea Wells - P&A for each subsea well was estimated as 32 days, and for fields with more than 1 wells, 1 in every 1 would require an additional 1 days. 3. Subsea Infrastructure Figure A3 shows the number of removal days to be utilised associated with subsea infrastructure, ranging from 15 days for less than 5Te structures to a maximum of 4 days for more than 2,1Te. Figure A3 - Subsea Infrastructure Removal Days by Weight (Te) Subsea Tonnage - 5 51-1, 1,1-2, >2,1 Removal Days 15 2 3 4 36 Decommissioning Supply Chain Capacity Report

4. Topside Removal - The duration of topside removal activities for each region was estimated based on durations as shown in Figure A4. Figure A4 - Topside Removal Duration for each Region (Vessel Days per Tonnage Range) Topside Tonnage 1,6 1,61-4, 4,1-8, 8,1-16, >16, CNS, NNS 1.25 3.75 6.25 12.5 27.5 IS (including EIS), SNS 1.25 3.75 5 - - 5. Substructure Removal - The duration of substructure removal activities for each region was estimated based on durations as shown in Figure A5. Figure A5 - Substructure Removal Duration for each Region (Vessel Days per Tonnage Range) Substructure Tonnage 1,6 1,61-4, 4,1-8, 8,1-16, >16, CNS 7 7 7 27 4 NNS - - 7 27 4 IS (including EIS) 7 7 7 27 - SNS 7 7 7 - - 6. Onshore remediation, dismantling and recycling - The duration of onshore decommissioning was also estimated based on the type of infrastructure and tonnage using the scale shown in Figure A6. Figure A6 - Onshore decommissioning duration by infrastructure type and weight Activity Te Ranges Days Subsea Infrastructures 2, 14 Substructures 1, - 1,5 28 Topsides 2, - 3, 28 37

For further information on this report please contact: Decom North Sea 21 Abercrombie Court, Prospect Road, Arnhall Business Park, Westhill, AB32 6FE T: +44 1224 9139 E: projects@decomnorthsea.com www.decomnorthsea.com 38 Decommissioning Supply Chain Capacity Report