Office for Nuclear Regulation

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EDF Energy Nuclear Generation Ltd (NGL) - Dungeness B (DNB) Planned Intervention

Executive summary

Purpose of intervention

This is a planned inspection at EDF Energy Nuclear Generation Ltd's (NGL's) Dungeness B (DNB) power station, undertaken as part of the planned intervention strategy for the Civil Nuclear Reactor Programme (CNRP) of the Office for Nuclear Regulation (ONR).

Interventions Carried Out by ONR

In relation to Licence Condition 7 (LC7) "incidents on the site" I considered two topics. The first was DNB's Corrective Action Programme (CAP), this included attending the Daily Screening Meeting (DSM). The second was DNB's OPerating EXperience (OPEX) process. The first topic was selected since it deals with DNB learning from its own CRs. The second topic was selected since it deals with DNB learning from the rest of the NGL fleet "internal OPEX" and from sources outside NGL "external OPEX".

In relation to Licence Condition 24 "operating instructions" I inspected Gas Circulator Maintenance Instructions (GCMIs). This topic was selected because of the safety significance of the Gas Circulators (GCs), because some GCMIs had been used during the recent periodic shutdown of Reactor 21 (R21), because of the large scope of the GC maintenance planned during the periodic shutdown of Reactor 22 (R22) in 2015 and because procedure quality is ONR issue 1592 at DNB.

In relation to Licence Condition 36 (LC36) "organisational capability" I considered two topics. The first topic was review of Management of Change (MoC) proposals. This topic was selected to sample application of DNB's arrangements to control any change to its organisational structure or resources which may affect safety. The second topic was review of Plant Life EXtension (PLEX) resourcing strategy. This topic was selected since NGL wish to make a decision about DNB PLEX by the end of 2014. If NGL decide to proceed with PLEX, a substantial number of investment projects will need to be delivered (the PLEX investment portfolio). For projects which will improve safety it is important that improvements are made in a timely manner so that risks are maintained As Low As Reasonably Practicable (ALARP). Organisational structures and resources will be an important factor influencing this.

I had a routine meeting with NGL's internal regulator [Independent Nuclear Assurance (INA)] and undertook information gathering.

Condition Reports (CRs) originating at DNB are considered at the DSM.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable.

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

In relation to LC7 and CAP, I considered that the DSM was effective and that the health of the CAP at DNB is adequate. In relation to LC7 and OPEX, I concluded that there was limited integration of NGL's OPEX process into DNB's or NGL's LC7 arrangements, which is not in line with ONR's guidance. I raised a corporate action relating to this. I also concluded that OPEX at DNB was adequate and improving. Taking all these factors into account I assigned an IIS Rating of 3 (adequate) to LC7.

In relation to LC24 I concluded that suggested amendments to GCMIs arising from the recent periodic shutdown of R21 had been captured and that the intent was to amend relevant GCMIs before the start of the periodic shutdown of R21 in 2015. I placed an action for DNB to describe the process that will be used. I identified no issues with a GCMI sampled and noted DNB's intent to improve the quality of GCMIs to be used in the periodic shutdown of R22 in 2015 that had not been used in the recent periodic shutdown of Reactor 21. I placed an action for DNB to describe the process that will be used. Taking all these factors into account I assigned an IIS Rating of 3 (adequate) to LC24.

In relation to LC36 and MoC proposals, I concluded based on the MoC information sampled that DNB's arrangements to control any change to its organisational structure or resources which may affect safety were being adequately implemented. In relation to LC36 and PLEX, I concluded that DNB has made good use of experience from other NGL stations which are currently delivering their PLEX investment portfolios and from delivery of major investment portfolios at DNB in the past to justify preferred organisational structures and resources. If NGL decide to proceed with PLEX, this work together with a future formal MoC proposal, will help ensure that safety improvements are made in a timely manner so that risks are maintained ALARP. Taking all these factors into account I assigned an IIS Rating of 3 (adequate) to LC36.

In relation to the other activities undertaken in this intervention, no key findings arose.

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

From the evidence obtained during this intervention, no matters have been identified that are likely to have a significant impact on nuclear safety on the station at this time. Therefore, no additional regulatory action arising from this visit is considered necessary at this time.