Not Protectively Marked NNB GENERATION COMPANY LTD The Choice of Interim Spent Fuel Management Storage Technology forforfor the Hinkley Point C UK EPRs Version Issue 1 Date of Issue 26 October 2011 Document No. NNB-OSL-STR-000034 © 2010 Published in the United Kingdom by NNB Generation Company Limited (NNB GenCo), 90 Whitfield Street - London, W1T 4EZ. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, including photocopying and recording, without the written permission of the copyright holder NNB GenCo, application for which should be addressed to the publisher. Such written permission must also be obtained before any part of this publication is stored in a retrieval system of any nature. Requests for copies of this document should be referred to Head of Management Arrangements, NNB Generation Company Limited (NNB GenCo), 90 Whitfield Street - London, W1T 4EZ. The electronic copy is the current issue and printing renders this document uncontrolled. Controlled copy-holders will continue to receive updates as usual. Not Protectively Marked Not Protectively Marked DODODOCUMENTDO CUMENT CONTROL Version Amendment Date Issue 1 Approved for issue 26 Oct. 2011 Not Protectively Marked NNB-OSL-STR-000034 Issue 1 October 2011 Page 2 of 37 Not Protectively Marked GLOSSARY EDF SA Électricité de France (EDF Energy’s parent company in France) EPR European Pressurised Water Reactor GDA Generic Design Assessment GDF Geological Disposal Facility GWd/t Gigawatt-days per tonne HPC Hinkley Point C IAEA International Atomic Energy Agency ISFS Interim Spent Fuel Store kW Kilowatt MADA Multi-Attribute Decision Analysis MOX Mixed Oxide MW(e) Mega-Watt (electrical) NDA Nuclear Decommissioning Authority NNB or NNB GenCo Nuclear New Build Generation Company (a subsidiary company of EDF Energy) PWR Pressurised Water Reactor RWMD Radioactive Waste Management Directorate (part of the NDA) SFA Spent Fuel Assembly Not Protectively Marked NNB-OSL-STR-000034 Issue 1 October 2011 Page 3 of 37 Not Protectively Marked CONTENTS 111 Introduction 222 Context for Spent Fuel Management at UK EPRs 333 TTTheThe CCChoicChoichoicee of SSSpentSpent FFFuelFuel MMManagementManagement TechnoloTechnologygy for the HHHinkleyHinkley PPPointPoint CCC UK EPREPRssss 444 The Timing of Construction 555 The Location of the Site 666 Conclusions 777 References Annex A --- Review of Hinkley Point C Interim Spent Fuel Store TechTechnologynology Choice in the Light of Fukushima A1A1A1 Introduction A2A2A2 Approach to the Review A3A3A3 Experience with the Spent Fuel Storage Facilities aatt FukushimaFukushima----11 during the accident A4A4A4 Relevant Characteristics of the Proposed HPC Spent Fuel Store A5A5A5 Discussion A6A6A6 ConcConclusionlusion Not Protectively Marked NNB-OSL-STR-000034 Issue 1 October 2011 Page 4 of 37 Not Protectively Marked 1 INTRODUCTION NNB Generation Company Limited (Company number 06937084), part of EDF Energy, is the Company that will lead the new nuclear programme in the UK. For the purpose of this report, NNB Generation Company Limited is referred to as EDF Energy. EDF Energy plans to build and operate two UK EPRs at the Hinkley Point C site in Somerset, England. Spent fuel from the UK EPRs will need to be managed from the time it is discharged from the reactor until it is ultimately disposed of and this will involve storing the spent fuel for a period in the fuel building and thereafter in a dedicated interim facility until it can be emplaced within the UK Geological Disposal Facility. EDF Energy has proposed that this interim store should be located on the Hinkley Point site which is consistent with UK policy. The Generic Design Assessment (GDA) process is examining the technical alternative options proposed by EDF and AREVA for interim spent fuel storage for a UK EPR to gain confidence that the ALARP and BAT requirements can be fulfilled by either wet or dry storage options. The choice of option for a specific location has been left open to the future licensee who is expected to take into account site specific issues. EDF Energy has considered the alternative options and has decided that for Hinkley Point C wet storage in pools provides the best solution for interim storage. In determining the best solution a range of factors including health and safety and environmental protection and performance were considered. The purpose of this report is to explain this decision and to demonstrate that the choice of wet storage technology for HPC is justified. The report also sets out the reasons for a different choice of interim storage to that proposed for Sizewell B, where dry storage has been selected. In addition this report fulfils the commitment made in EDF Energy’s response to the ONR Chief Inspector’s interim report on the implications of the Fukushima accident to revisit the choice of the interim storage technology for Hinkley Point C. This is provided in Annex A to the report. Not Protectively Marked NNB-OSL-STR-000034 Issue 1 October 2011 Page 5 of 37 Not Protectively Marked 2 CONTEXT FOR SPENT FUFUELEL MANAGEMENT AT UK EPRS 2.1 UK POLICY ISSUES In its 2008 White Paper 1 the government stated: “Having reviewed the arguments and evidence put forforward,ward, and in tthehe absence of any proposals from industry, the Government has concluded that any new nuclear power stations that might be built in the UK should proceed on the basis that spent fuel will not be reprocessed and that plans for, and financing of, waste managemanagemmentent should proceed on this basis. We are not currently expecting any proposals to reprocess spent fuel from new nuclear power stations. Should such proposals come forward in the future, they would need to be considered on their merits at the time and the Government wouldwould expect to consult on them.” The UK Government is implementing a carefully developed strategy leading to the construction of a Geological Disposal Facility (GDF) for higher activity radioactive waste and spent fuel. In its Managing Radioactive Waste Safely White paper 2, the UK Government acknowledges that, although spent fuels are not currently classified as waste, they may need to be managed through geological disposal. The NDA is taking into account the possible inclusion of these materials within the design and development of the geological disposal facility. The disposability assessment carried out by the NDA’s Radioactive Waste Management Directorate (RWMD) for the UK EPR as part of the GDA process3,4 concluded that, compared with legacy wastes and existing spent fuel, no new issues arise that would challenge the fundamental disposability of the spent fuel expected to arise from operation of the UK EPR. This conclusion is supported by the similarity of these materials to those expected to arise from the existing PWR at Sizewell B. Given a disposal site with suitable characteristics, the spent fuel from the UK EPR is expected to be disposable. The time that would be required for the safe and secure interim storage of spent fuel prior to disposal depends on a two key factors: • the availability of a Geological Disposal Facility (GDF); and • the requirement that spent fuel characteristics are suitable to allow disposal to the GDF (i.e. the spent fuel has sufficiently cooled to allow its emplacement). With regard to the availability of a GDF, RWMD have published their plans and timescales for the expected implementation of the GDF 5. The current projection is that the UK GDF would become available around 2040 for the disposal of legacy ILW and 2075 for the start of emplacement of legacy spent fuel and HLW. It is assumed that ILW would be disposed of before 1 Her Majesty’s Government, “Meeting the Energy Challenge: A White Paper on Nuclear Power”, Cmnd 7296, January 2008 2 Managing Radioactive Waste Safely White Paper 3 Geological Disposal: Generic Design Assessment: Summary of Disposability Assessment for Wastes and Spent Fuel arising from Operation of the UK EPR. NDA Technical Note no. 11261814. 4 See also Annex B to the National Policy Statement for Nuclear Generation. 5 Geological Disposal – Steps towards implementation, March 2010, NDA/RWMD/013. Not Protectively Marked NNB-OSL-STR-000034 Issue 1 October 2011 Page 6 of 37 Not Protectively Marked HLW and spent fuel and that waste and spent fuel from existing facilities would be emplaced in the GDF before material from new stations. This schedules the end of legacy spent fuel disposal to the GDF in around 2130. Thereafter the GDF could be available to dispose of spent fuel from Hinkley Point C. Regarding disposability of spent fuel, recent work undertaken by RWMD 6 on behalf of the Nuclear Industry Association (NIA) has concluded that the spent fuel from the UK EPR could be suitable for disposal in the UK reference case GDF (based on the Swedish KBS-3V design) after approximately 50 years of storage post end of generation. It is therefore assumed that the date for start of transfer of spent fuel from the interim store to a GDF is around 2130. The process of transfer will take approximately 10 years and therefore all fuel would be expected to be removed from interim storage by around 2140. The precise timescales for which spent fuel will need to be stored remain subject to some uncertainty. EDF Energy is proceeding on the prudent basis that facilities could be needed to provide safe storage for spent fuel over timescales that extend well beyond the lifetime of the reactors themselves. There is currently no centralised storage facility for spent fuel in the UK, other than the pools tied to the reprocessing plants at Sellafield whose capacity is limited, and there are currently no plans in the UK to build a new centralised storage facility. EDF Energy plans, therefore, to store spent fuel from its UK EPRs at the site where it is produced and to seek the required Development Consent and regulatory permits and licences for these stores as part of the application for the power stations themselves; this approach is consistent with the Government’s “base case” (described in Section 4 of the Government’s 2008 Consultation on Funded Decommissioning Programme Guidance for New Nuclear Power Stations 7).