Office for Nuclear Regulation

Dungeness B - Unannounced LC32 inspection

Executive summary

Purpose of Intervention

This was a planned intervention at Dungeness B Power Station, operated by EDF Energy Nuclear Generation Limited (EDF NGL) in accordance with ONR’s Intervention Plan for the site. 

This was an unannounced intervention to assess EDF NGL’s compliance with Licence Condition (LC) 32 (accumulation of radioactive waste) that was undertaken with the nominated site inspector and a radiological waste specialist inspector.  This is a follow-up inspection based on the findings of a previous inspection carried out in April 2019 (ONR-OFD-IR-19-006). 

In addition to this compliance inspection, the nominated site inspector also undertook a number of routine engagements with the site.

Interventions Carried Out by ONR

The intervention focused on compliance against LC32, in particular progress to address level 3 regulatory issue 5113.  The following ONR guidance was used as the basis for the inspection:

The nominated site inspector undertook the following activities:

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

This was an unannounced LC32 compliance inspection.  The focus of the inspection was the Licensee’s progress against the radioactive waste management plan, which was developed to address the shortfalls captured in a regulatory issue and an associated enforcement letter was seeking evidence that the station improvements identified during my previous inspection in April 2019 had been sustained.  

I sampled progress against the five year radioactive waste management plan.  The station is on track to deliver the actions identified for this year.  Funding and resources are secured to support delivery of the future work within the radioactive waste management plan. Progress against the plan is reviewed regularly through the Environmental Safety Review Group.

During the walk-down of the facilities, I noted that the significant improvements to the Decontamination Centre which I had observed in April 2019 had been sustained. Whilst, there are improvements still required to some of the waste storage areas, these are captured within the radioactive waste management plan. 

I identified one minor shortfall in relation to the management of the neutron scatter plugs temporarily stored in storage cannons with the decontamination facility.   This is a minor shortfall and has therefore raised a regulatory issue to follow the station’s progress in addressing it.

Based on the evidence sampled, I judge that the site has now established appropriate governance, funding and resources in place to continue to deliver the radioactive waste management improvements required. I consider that the regulatory issue 5113 can be closed.  Compliance against LC32 will be considered as part of routine regulatory oversight.  I judge that a GREEN rating is appropriate.      

 I, the nominated site inspector followed up two events that were reported to me by the station relating to valve mal-operation and a level1 safety rules event. In relation to the forma, I have raised a regulatory issue in order for the station to provide further details into this event.  In addition, I also attended the station’s Emergency Arrangements Review Meeting (EARM) which looked at the station’s last 12 months performance and its future planning for level 1 exercises.

I also observed the simulator training of C shift team for a loss of grid power event resulting in a double reactor trip. This scenario tested the team’s response with the new reactor 22 simulator. I observed a good and confident response to the event by the team in their ability to control the situation as it developed.

Conclusion of Intervention

In relation to compliance against Licence Condition 32, there are no findings from this intervention that could undermine nuclear safety at this time.  Therefore, no additional regulatory action is needed over and above the planned interventions at Dungeness B power Station.