UK ABWR Generic Design Assessment

1 Form10/00. UK ABWR. Document ID : GA91-9101-0101-32000. Document Number : FRE-GD-0008. Revision Number : C. UK ABWR Generic Design Assessment Generic PCSR Chapter 32 : Spent Fuel Interim Storage hitachi -GE Nuclear Energy, Ltd. NOT PROTECTIVELY MARKED. Form01/03. UK ABWR. Page ii / ii DISCLAIMERS. Proprietary Information This document contains proprietary information of hitachi -GE Nuclear Energy, Ltd. ( hitachi -GE), its suppliers and subcontractors. This document and the information it contains shall not, in whole or in part, be used for any purpose other than for the Generic Design Assessment (GDA) of hitachi -GE's UK ABWR. This notice shall be included on any complete or partial reproduction of this document or the information it contains.

2 Copyright No part of this document may be reproduced in any form, without the prior written permission of hitachi -GE Nuclear Energy, Ltd. Copyright (C) 2017 hitachi -GE Nuclear Energy, Ltd. All Rights Reserved. GA91-9101-0101-32000 NOT PROTECTIVELY MARKED. NOT PROTECTIVELY MARKED. Form05/01. UK ABWR Generic Pre-Construction Safety Report Revision C. Table of Contents Executive Summary .. ii Introduction .. Background .. Document Structure .. Purpose and Scope .. Purpose .. Scope .. Spent Fuel Storage Strategy .. Process Description .. Operational Experience (OPEX) .. System Description .. Design Basis .. Concept Systems, Structures and Components (SSCs) Design .

3 System Performance and Safety Safety Provision for SFIS Safety Claim : Functions to Maintain Spent Fuel Temperature .. Safety Provision for SFIS Safety Claim : Functions to Provide Containment Barrier .. Safety Provision for SFIS Safety Claim : Functions to Maintain Sub-criticality of Spent Fuel .. Safety Provision for SFIS Safety Claim : Functions to Provide Radiation Shield .. Safety Provision for SFIS Safety Claim / SFIS Safety Claim : Functions to Provide Handling and Retrievability / Function to Limit Deceleration Loading to Canister Containment Boundary .. Internal External Hazard .. Fault Identification and Definition .. Spent Fuel Management at the End of Generation.

4 EMIT and AMP .. Removal from Site .. Decommissioning Plan .. Spent Fuel Management Arrangements for SFIS .. Records Management .. Change Control .. Assumptions, Limits and Conditions for Operation .. Purpose .. LCOs Specified for SFIS System .. Assumptions for SFIS System .. Summary of ALARP Justification .. Conclusions .. References .. Appendix A.. A-1. 32. Spent Fuel Interim Storage Table of Contents Ver. 0 i NOT PROTECTIVELY MARKED. NOT PROTECTIVELY MARKED. Form05/01. UK ABWR Generic Pre-Construction Safety Report Revision C. Executive Summary This chapter presents the high level safety case for the UK ABWR Spent Fuel Interim Storage (SFIS).

5 System concept Design . The chapter does not specify Safety Functional Claims or Safety Property Claims, but instead it lists a number of high level SFIS safety claims at an appropriate level for GDA. These claims have been derived from the High Level Safety Functions (HLSFs) of the UK ABWR, which are set out in PCSR Chapter 5 : General Design Aspects. The safety cases for SFIS in this chapter together with Spent Fuel Export in PCSR Chapter 19 : Fuel Storage and Handling demonstrate that the SFIS system can be safely integrated in to the UK ABWR, and that risks associated with the Design and operation of the SFIS systems for the UK ABWR are capable of being reduced ALARP.

6 It should be noted that the detailed Design for SFIS Systems, Structures and Components (SSCs) has not been completed during GDA. Furthermore, because SFIS operations will not commence for a number of years into station operation, it is not considered appropriate to identify a specific SFIS. supplier or system during GDA. This approach will allow the future licensee to adopt benefits from future advances in technology and ensure modern standards are applied at the appropriate time for SFIS. This is in line with UK regulatory advice. Therefore this chapter provides proof of the concept of SFIS as part of the overall UK ABWR Design and demonstrates that options to the future licensee are not foreclosed.

7 The approach adopted for GDA. is to present a SFIS Design for the UK ABWR that is based on current commercially available technology as a concept SFIS system, but which still allows the future licensee to take advantage of relevant good practice and technology which may become available in the future. The concept Design of the SFIS is sufficiently developed throughout the world to enable a high level Assessment of the risks associated with SFIS operations. A high level safety analysis has been undertaken for GDA and shows that the SFIS system is robust and tolerant to faults. This chapter demonstrates that a SFIS system can be safely integrated into the overall UK ABWR.

8 Design and that the risks associated with its operation are capable of being reduced As Low As Reasonably Practicable (ALARP). It is acknowledged that further work will be required post-GDA to develop the SFIS system Design and fully incorporate site specific aspects. This work will be the responsibility of any future licensee. 32. Spent Fuel Interim Storage Executive Summary Ver. 0 ii NOT PROTECTIVELY MARKED. NOT PROTECTIVELY MARKED. Form05/01. UK ABWR Generic Pre-Construction Safety Report Revision C. Introduction This PCSR chapter focuses on the Generic Design aspects of the SFIS system for the UK ABWR. Spent fuel will be generated from the UK ABWR; it will first be stored in the spent fuel pool inside the reactor building for 10 years, after which it will be transferred to the SFIS facility for the time period required to cool the fuel to a suitable temperature for final geological disposal.

9 Similar to radioactive waste, the accumulation of spent fuel will be minimised, and the radiological risks are considered in the Design . The spent fuel strategy described in this chapter follows the UK Government Funded Decommissioning Programme (FDP) Guidance [Ref-1] base case assumption that the spent fuel from new nuclear power stations will be disposed of in the Geological Disposal Facility (GDF) that the UK. Government will construct to dispose of Higher Activity Wastes (HAW). The anticipated timescales for the management of spent fuel extend long after the reactor has ceased operation. The UK ABWR. is designed by hitachi -GE to ensure safety at all times across all plant activities.

10 This includes the spent fuel export steps from the reactor building and, all activities associated with interim storage until spent fuel is removed for final disposal in the GDF. This therefore ensures safety related to spent fuel at all times, until safe final disposal. The spent fuel is stored in accordance with good engineering practice and the principle of passive safety. In order to ensure continued safe interim storage, spent fuel should be repackaged into a form suitable for transportation to, and safe disposal in, the GDF. A disposability Assessment considering spent fuel generation, its safe management and subsequent treatment concluded that spent fuel could be disposed of in the GDF [Ref-23].