Office for Nuclear Regulation

Dungeness B - Licence Condition Compliance inspection of LC7, 26 and 28

Executive summary

Purpose of Intervention

The purpose of this intervention was to undertake Licence Condition (LC) compliance inspections at EDF Energy Nuclear Generation Limited (NGL) Dungeness B (DNB) Power Station in line with the planned inspection programme contained in the DNB Integrated Intervention Strategy (IIS) for 2018/19.

Interventions Carried Out by ONR

As part of this intervention I, the nominated site inspector, and the outage project inspector, carried out a planned compliance inspection against LC7 (Incidents on site) and LC26 (Control and supervision of operations). In addition to the planned compliance inspections a reactive unplanned compliance inspection was undertaken for LC28 (Examination, inspection, maintenance and testing). This intervention was also supported by an ONR specialist conventional health and safety inspector who undertook a two day conventional health and safety (CHS) inspection.

I also observed and took part in the licensee’s Rapid Trending Review (RTR) for the DNB reactor 22 periodic shutdown. The compliance inspections complemented the licensee’s own RTR inspections being undertaken by NGL’s internal safety regulator (Independent Nuclear Assurance, INA). The aim of the RTR is to identify performance shortfalls in the early stages of an outage to enable station management to reduce or eliminate undesirable behaviours and conditions which could have an adverse impact on outage success. 

The above interventions were also observed by a representative from the Department for Business, Energy and Industrial Strategy (BEIS) over a two day period to gain a deeper understanding of the role of an ONR site inspector.

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

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable: No safety system inspection was undertaken during this intervention.

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

I participated in the DNB (Reactor 22) planned outage Rapid Trending Review (RTR) process which aims to identify performance shortfalls in early stages of the outage. The focus of the RTR was safety and quality, specifically in the areas of safety rules/ configuration management, fire safety and industrial safety. An outcome of the RTR was that INA raised three areas for improvement (AFI’s) and three opportunities for improvement (OFI’s). AFI’s and OFI’s are part of INA’s processes for addressing shortfalls.

My planned interventions against LC7,  LC26 and reactive unplanned LC28 compliance inspections identified the following:

LC7 – The reporting of incidents at site is actively encouraged and is inclusive for the contract partners that work at the station. Evidence of organisational learning from condition reports raised at the station is demonstrable from the licensee’s quarterly station trend report.  Trending of particular areas of interest is undertaken to prevent reoccurrence. Based on my sampled inspection I have judged that the DNB arrangements meet the requirements of LC7 I have therefore rated this inspection as Green, no further regulatory action is required.

LC26 & 28 – Overall, I observed positive examples of  individuals being set to work and appropriately supervised, however, there were also examples where this was not apparent which included some poor behaviours. In addition, I also observed positive examples of the use of maintenance instructions, safety documentation and verification processes, however, there were examples of Procedural Use and Adherence to hold points in Quality Plans not being followed. In addition, I noted significant shortfalls in the supervision and control of waste material leaving the radiological controlled area.  The ONR outage inspector judged that there were good quality assurance initiatives in place, including identifying quality control issues from previous outages and engagement with supply chain, but noted that there was room for improvement regarding implementation of quality assurance arrangements.

Noting that the INA RTR team has identified three areas for improvement (AFI’s ) (equivalent to an ONR Amber rating) to address the above shortfalls, I am content that the internal regulator will follow these areas to monitor the station’s progress in  addressing them during the outage . Therefore, I have rated this inspection as Amber but with no further regulatory action required by ONR. 

I also followed up a reported event regarding the uncertain position of a grey control rod which took place on 29th June 2018. The licensee’s investigation report provided to ONR was not clear in either its findings or the rational for the actions that were proposed.  I have therefore raised a regulatory issue to track the station’s progress in addressing my comments regarding its investigation report.

The key regulatory activities undertaken during the two day conventional health and safety (CHS) inspection were based around:

Whilst examples of good standards were found during the inspection, areas where improvements are required were also identified. Improvements are required in asbestos management, specifically in training and provision of information for work specifiers. Also, improvements to workplace transport safety are also required in a number of areas of the station to facilitate pedestrian/vehicle segregation. In light of these observations two regulatory issues have been raised to track the station’s progress in making the required improvements.

Conclusion of Intervention

I found that the RTR is an effective means to identify a range of good practice and emergent safety issues, both conventional and nuclear, and that undertaking the process early within the outage provides the station with the opportunity to act upon the findings made. I therefore consider that the requirements as identified within NGL’s own arrangements for RTR’s have been met.

The inspection of INA is not subject to scoring as part of the IIS; however, I have judge the performance of INA in undertaking the RTR for DNB was good.

Overall, I consider that the arrangements and their associated implementation for LC7 meet legal requirements and have therefore rated this inspection as Green. For the LC26 and LC28 compliance inspections I have rated them both as Amber however given that the licensee’s own internal regulator INA RTR team has also identified these as significant shortfalls during the inspection, I am therefore content for the INA RTR team will follow these areas to monitor the station’s progress in addressing them during the outage.

There are no findings from this inspection that could significantly undermine nuclear safety nor require a change to the planned interventions and inspections of DNB.