Office for Nuclear Regulation

ONR readiness / compliance inspection in support of permissioning Dry Fuel Store Safety Case Stage Submission 1 Rev 1 covering Structural Integrity and Radiological Protection

Executive summary

Purpose of intervention

This was a planned Office for Nuclear Regulation (ONR) inspection to evaluate EDF Energy Nuclear Generation Ltd (EDF Energy) in the development and implementation of its Sizewell B Dry Fuel Store Safety Case, Stage Submission 1 Revision 1 (SS1 Rev 1).  This work supports ONR’s permissioning of Dry Fuel Store Sizewell B activities.

Interventions Carried Out by ONR

The inspection focus was to gather evidence to support future regulatory decision-making in relation to the Dry Fuel Store activities at Sizewell B.  Licence Instruments giving ONR’s Approval of Dry Fuel Store Safety Case Operating Rules (limits and conditions identified in the interest of safety) and Consent to commence active commissioning will eventually be required.  This inspection builds on ONR’s assessment work to date on safety claims and justification presented in SS1 Rev 1.  Intervention activities were structured around compliance with the following Nuclear Site Licence Conditions:

Explanation of Judgement if Safety System Not Judged to be Adequate

This was not a planned Safety System Inspection and no judgement was made.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

Overall this inspection was considered to be positive.  No serious issues were identified that challenged ONR’s current assessment of SS1 Rev 1 or its implementation.  Three out of the 5 LCs inspected against were awarded ratings of below standard on the grounds that although fundamental principles were considered to have been met,  there was no evidence to justify a rating of adequate as documents were still being drafted or were under-developed.  I considered there was a lack of evidence to demonstrate that EDF Energy Subject Matter Experts had reviewed information justifying individual’s abilities or the adequacy of procedures to be worked against.  This is a requirement to demonstrate EDF Energy is acting as an informed knowledgeable customer.  EDF Energy has plans in place to progress the documentation and hence no issues have been raised.

There is still time to address identified gaps although this is decreasing rapidly given time pressures created by the project.

Conclusion of Intervention

This inspection was considered positive but highlighted the need for EDF Energy Project and Commissioning managers to be vigilant and maintain a clear focus on quality and demonstrate that EDF Energy is an informed, knowledgeable customer.