International Atomic Energy Agency

International Safety Standards forthe Storage of Spent Fuel

PHIL METCALF

International Conference on Management of Spent Fuel from Nuclear Power Reactors

Vienna 31 May – 4 June 2010

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• Safety standards developments• Increased enrichment• Increased burn up• Advanced fuel design • MOX • Re-racking• Burn up credit • Storage > design lifetimes

Developments since 1994Developments since 1994

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Safety Case & Assessment Predisposal

DS 248

Storage of SpentNuclear Fuel

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1. Government responsibilities2. National policy & strategy3. Regulatory responsibilities4. Operator responsibilities5. Safety/Security6. Interdependences7. Management systems8. Waste minimization9. Characterization and

classification10. Waste treatment11. Waste storage12. Waste acceptance for

processing, storage and/or disposal

13. Prepare safety case and supporting safety assessment

14. Safety case scope and regulatory compliance

15. Safety case documentation

16. Periodic safety review17. Facilities location and design 18. Facility construction and

commissioning 19. Facilities operation, maintenance,

emergency preparedness 20. Decommissioning 21. Nuclear safeguards 22. Existing facilities

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1. INTRODUCTION

2. PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

3. ROLES AND RESPONSIBILITIESGENERALGOVERNMENTOPERATORSAFEGUARDS & PHYSICAL PROTECTION SYSTEMS

4. MANAGEMENT SYSTEMSPENT FUEL MANAGEMENTRESOURCE MANAGEMENTPROCESS IMPLEMENTATION

5. SAFETY CASE AND SAFETY ASSESSMENTDOCUMENTATION OF THE SAFETY CASE

6. GENERAL SAFETY CONSIDERATIONS FOR STORAGE OF SPENT FUELGENERALDESIGN COMMISSIONING OPERATION DECOMMISSIONING

Storage of SpentNuclear Fuel

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APPENDICESI SPECIFIC SAFETY CONSIDERATIONS WET & DRY STORAGE

II CONDITIONS FOR SPECIFIC FUEL TYPES

ANNEXES

I SHORT TERM AND LONG TERM STORAGE

II OPERATIONAL SAFETY CONSIDERATIONS FOR WET AND DRY STORAGE

III EXAMPLES OF OPERATING PROCEDURES

IV RELATED IAEA SAFETY STANDARDS PUBLICATIONS

V SAFETY ASSESSMENT (EXTERNAL NATURAL PHENOMENA)

VI SAFETY ASSESSMENT (EXTERNAL HUMAN INDUCED PHENOMENA)

VII POSTULATED INITIATING EVENTS (INTERNAL PHENOMENA)

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GENERALGENERAL

• May be considered waste or resource – safety issues the same – differing circumstances;• Open fuel cycle – direct disposal • Closed fuel cycle – reprocessing • Uncertain• All involve storage – months to decades• Sometimes uncertain lifetime• Wet or dry storage (facility or casks)

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• Safety ensured by: • Containment of radionuclides • Criticality safety• Heat removal• Radiation shielding • Inspection and retrievability

• Functions ensured by• Proper siting/location • Design• Construction and commissioning • Operation • Decommissioning (considered in design)

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• Storage not ultimate solution • Requires end point e.g. reprocessing or

disposal to ensure safety • NPP design lifetime - few decades• +/-50 y experience of storage • +/-100 years design lifetimes used • Considering rate of industrial and

institutional change, periods beyond 50 y deemed ‘long term’ in the context of this Safety Guide

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• Up-to-date guidance on design, operation and safety case for all storage facilities

• Consider different fuel types NPP & RRs• Different periods, including > design lifetime • Guidance to meet Safety Requirements:

• Safety of Nuclear Fuel Cycle Facilities• Predisposal Management of Radioactive Waste• Safety Assessment for Facilities and Activities • Management System for Facilities and Activities

OBJECTIVEOBJECTIVE

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SCOPESCOPE

• Co-located • Own sites• Not specifically operational storage• Water cooled, others e.g. gas cooled, RR • Degraded or failed fuel in canisters• No detailed guidance on physical protection • Security/safeguards interactions

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• Workers and public• Present and future generations• Normal and accident conditions• Justification• Dose and risk limitation - constraints• Optimization of protection

Basic Safety StandardsBasic Safety Standards

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Safety Case & Assessment Predisposal

DS 248

Safety CaseSafety Case

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System DescriptionSite and waste characteristics, Safety Functions, Design Options

Safety Case Context• Safety objectives• Safety principles • Regulations

Safety Strategy• Waste treatment, minimization• Interdependencies•Shielding, containment,•Defence in depth

Integration of Safety ArgumentsNormal operation, anticipated operational ocurrences, accidents,

waste treatment and waste productN

on radiological Environm

ental Im

pact

Non-radiological

Operational Safety

Site / Engineering

Assessments

Stakeholder & Regulatory Involvem

ent

Limits, controls & conditions

Managem

ent of uncertainty

Iteration and design optimozatio

Managem

ent System

Managem

ent System

Radiological impact

Models

Calculations

Scenarios

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ConclusionConclusion

• Guidance on:• Roles and responsibilities• Design• Operation• Decommissioning • Safety case

• Need for inter-comparison and harmonization of use

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