Office for Nuclear Regulation

Winfrith – Inspection ID: 52878

Executive summary

Date(s) of inspection

  • October 2023

Aim of inspection

The aim of this inspection is to gain assurance that ML Winfrith has appropriate arrangements for the commissioning of any plant or process which may affect safety.
The inspection will also seek to gain assurance that commissioning of the DRAGON reactor core segmentation operations are undertaken in accordance with those arrangements and that they are undertaken under the control and supervision of suitably qualified and experienced persons appointed for that purpose in accordance with the license conditions LC21(5) and LC12.

Note that the review of arrangements will have equal applicability to the SGHWR commissioning 2024.

Subject(s) of inspection

  • LC12 – Duly authorised and other suitably qualified and experienced persons – Rating: Green
  • LC21 – Commissioning – Rating: Amber

Key findings, inspector’s opinions and reasons for judgement made

This inspection assessed Magnox Ltd Winfrith’s arrangements to support commissioning of the Dragon Core Segmentation project and sampled the implementation of those measures on site. Compliance was assessed against Licence Condition 21 “Commissioning” using relevant Office for Nuclear Regulation (ONR) inspection guidance, specifically Technical Inspection Guide (TIG) NS-INSP-GD-021 Issue 7.1.

This was a planned inspection at the Magnox Ltd Winfrith Site. The inspection was undertaken as part of the intervention strategy for the Decommissioning, Fuel and Waste (DFW) Sub-Division.

During the inspection Management of the commissioning tests was sampled and confirmed in line with the commissioning schedules. It was also confirmed that the commissioning schedules have adequately captured the safety case requirements.

The commissioning team were knowledgeable and understand what commissioning work is required from a technical perspective.

Whilst testing against the commissioning schedule was adequately managed, the project could not demonstrate oversight and administration of certain related commissioning activities including training, concession management, operating instructions proving etc. Such activities are being conducted including areas of good practice. However, without systems in place to monitor and oversee these activities, it is not possible to determine if the entirety of the activities are adequately captured or managed.

I have rated the LC21 inspection as amber “Seek Improvement” due to the number of areas for improvement raised centred on project controls for oversight and administration of commissioning related activities.

Appropriate appointments have been made under LC21(5) and LC12 for commissioning. Individuals with oversight of testing are suitably qualified and experienced. I have therefore rated LC12 Green “No formal action”.

Conclusion

Management of the commissioning tests was confirmed in line with the commissioning schedules and that those schedules have captured the safety case requirements.

Although it was evident that the commissioning team were knowledgeable, understand what commissioning work is required from a technical perspective, there are areas where there were no clear administration and oversight of certain commissioning activities including training, concession management, operating instructions proving etc, although such activities are being conducted.   Without systems in place to monitor these activities, it is not possible to determine if the entirety of the activities are adequately captured or managed without 100% sampling.  As an example, whilst it is clear that operator familiarisation and practical training activities are occurring, without adopting a systematic approach it is unclear if such activities cover all roles that affect safety and if they will prove sufficient for the post requirements.

Establishing oversight of these commissioning activities will be an enabler to project handover since it will provide evidence that the activities have been fully identified and completed.

I have rated the LC21 inspection as amber “Seek Improvement” due to the number of areas for improvement raised centred on project controls for oversight of commissioning related activities.

Appropriate appointments have been made under LC21(5) and LC12 for commissioning. Individuals with oversight of testing are suitably qualified and experienced. I have therefore rated LC12 Green “No formal action”.