Office for Nuclear Regulation

Planned System Based Inspection (SBI 19) Fuel Handling (SZB System “KE”) and Licence Condition 7

Executive summary

Purpose of intervention

The purpose of this intervention was to undertake a system based inspection (SBI) and a site licence compliance inspection at EdF Nuclear Generation Ltd’s (EdF NGL) Sizewell B (SZB) power station.  The System inspected was System 19 – “Fuel Handling” (also described as System “KE” at SZB), and the inspection was conducted in line with the inspection programme contained in the SZB integrated intervention strategy (IIS) for 2015/16.  The site licence compliance was licence condition 7.    

Interventions Carried Out by ONR

The ONR Site Inspector and I (together with an inspector from the Polish Nuclear Regulatory Authority), referred to as “we” within this report, conducted an SBI of System 19 (Fuel Handling) at SZB nuclear power station.  Through examination of this system, we performed compliance inspections against the following licence conditions of the Nuclear Site Licence i.e. LC 10: Training; LC23: Operating Rules; LC24: Operating Instructions; LC27: Safety Mechanisms, Devices and Circuits; LC28: Examination, Inspection, Maintenance and Testing and LC34: Leakage and Escape of Radioactive Material.  The inspection was based on sampling the implementation of the arrangements in place at the station against each licence condition.  The ONR Site Inspector also undertook a routine LC 7; Incidents on the site, inspection as part of this intervention.

Explanation of Judgement if Safety System Not Judged to be Adequate

From the inspection we judged that overall the fuel handling system met the requirements of the safety case and is adequate.

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

 LC 10 (Training) – We sampled the training records for a number of key fuel route personnel finding the training records for all personnel sampled to be fully in order.  The role and training profile for the Fuel Route Duly Authorised Person (DAP) was also examined and found to be of an adequate quality.  We also sampled the authorisation of a fuel route DAP and again found this to be in order.  Consequently compliance with LC 10 was judged to be adequate with an Integrated Intervention Strategy (IIS) rating of 3.

LC 23 (Operating Rules) – We sampled the licensee’s compliance with a number of key Fuel Storage Pond (FSP) surveillances, under its Technical Specifications (Tech Specs).  All records examined indicated that these surveillances had been adequately completed and had been accurately recorded.  Accordingly, we judged that compliance with LC 23 was adequate meriting an IIS rating of 3.

LC 24 (Operating Instructions) – During this part of the inspection we sampled the Criticality Safety Notices (CSNs) on the plant and compliance with these documents; we also sampled compliance with the procedure for inspection of new fuel receipts.  All documentation we examined was found to be in order and where CSNs were encountered on the plant, operations in that area were found to be in compliance with the requirements of the CSNs.  We therefore judged that compliance with LC 24 was adequate, meriting an IIS rating of 3.

LC 27 (Safety Mechanisms, Devices and Circuits) – We examined the licensee’s procedure for defeat of interlocks and were content that this appears to be adequately robust.  Compliance with LC 27 was hence judged to be adequate with an IIS rating of 3.

LC 28 (Examination, Inspection, Maintenance and Testing) – We examined a selection of maintenance records for key equipment within system “KE” and generally found the documentation to be in order.  However, we asked the licensee to consider the addition of appropriate routines for inspection/maintenance of lifejackets and maintenance of the fortress key interlocks on the pond gates.  We noted the licensee’s ongoing work to demonstrate the material condition of its Boral neutron absorbing sheets within the fuel racks installed in the Fuel Storage Pond.  Overall we considered compliance with LC 28 was adequate and awarded an IIS rating of 3.

LC 34 (Leakage and Escape of Radioactive Materials and Radioactive Waste) – Examination of the findings of the licensee’s investigation of a recent minor leak into the sump from the Flask Fill Bay indicated that a thorough investigation had been conducted, the problem had been diagnosed and a temporary solution had been effected.  The licensee provided evidence showing that detailed optioneering has been conducted to deliver a more permanent solution.  However, we did provide advice to the licensee that we wished to see progress with projects to install a new level detection device in the pond (capable of measuring water levels down to the base of the pond) and with a more robust engineered feature to remove active filters from the Refuelling Cavity and to place these into a shielded storage drum in-situ.  We judged that compliance with LC 34 was adequate, with an IIS rating of 3.

LC 7 (Incidents on site) – The site Inspector sampled the arrangements for compliance with LC 7.  He found that the licensee has comprehensive processes for the notification, recording, investigation and reporting of incidents occurring on the site.  The continuous improvement programme also encompasses external learning and self-assessment in line with expected good practice.  From the records seen and the discussion held with station personnel, he considers that the arrangements sampled for compliance with LC7 are adequate, with an IIS rating of 3 and with no regulatory issues being raised.

The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.

Conclusion of Intervention

After considering all the evidence examined during the sample inspections undertaken against LCs 10, 23, 24, 27 and 28, we considered that the fuel handling systems (System “KE”) met the requirements of the safety case.

From the information gathered and evidence obtained during this intervention a number of minor areas for improvement were raised with the licensee, which the licensee accepted and will be tracked and closed as a part of the ONR Site Inspector’s normal regulatory business.  However, no matters were been identified that are likely to have significant impact on nuclear safety on the station at this time. Therefore we consider that no additional regulatory action arising from this visit is necessary currently, and the interventions for SZB power station, set out in the integrated intervention strategy, should continue to be implemented as planned.