Sizewell B planned Intervention
- Site: Sizewell B
- IR number: 17-185
- Date: December 2017
- LC numbers: 26
Purpose of Intervention
The purpose of this intervention was to undertake Licence Condition (LC) compliance inspections at EDF Energy Nuclear Generation Ltd's (NGL's) Sizewell B power station, in line with the planned inspection programme of the Operating Facilities Operating Reactors sub-programme intervention plan for 2017/18.
Interventions Carried Out by ONR
During this intervention I:
- Attended the biannual emergency preparedness consultation committee (EPCC)
- Attended the Sizewell Site Stakeholder Group (SSG) meeting
- Undertook a monthly review of safety with the station independent nuclear assurance (INA) team and reviewed the status of the outage with the Technical Safety Support Manager (TSSM)
- Undertook a general inspection of work being undertaken in containment and examined the control and supervision of work.
Explanation of Judgement if Safety System Not Judged to be Adequate
No system inspection was undertaken during this intervention.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
At the time of my visit the first stage of machining affected steam generator welds was nearing completion. Subsequent to this the Barnwood design authority has identified three candidate repair options, all of which necessitate removal of the drain line capability. ONR specialist inspectors are continuing to monitor the output from the company's structural integrity panel.
The station notified me during this visit that an internal personal contamination event in which a contractor received an internal dose when undertaking invasive work on steam generator D. This will be subject to an adverse condition investigation and ONR will receive an INF 1 notification in accordance with arrangements under LC 7.
During my inspection of containment I made the following observations:
- The majority of work has now been de-mobilised with the exception of ongoing steam generator recovery work (which I did not examine due to dose and contamination restrictions) and final structural weld repairs to the 21m level (in light of damage incurred by the multi-stud tensioner during RO14). General lighting and housekeeping around containment was to a high standard and the remaining laydown areas maintained appropriately. I noted during the tour clear use of radiation hotspot and low dose zones to discourage loitering and unnecessary dose uptake.
- I examined the work order card for welding activities being undertaken as part of 21m level structural repairs. An appropriately designated fire watcher was in place and I was satisfied the work pack had an appropriate method statement and requisite quality plan governing the work. One of the welders described the task and was able to articulate the hazards associated with hot work and mitigations in place. I examined a time out for personal safety checklist completed as part of the pre job brief. The EDF sponsoring engineer was present at the workface and demonstrated appropriate licensee supervision of this work. The Doosan Babcock supervisor was acting as line and field supervisor and was complimentary to the close EDF oversight and supervision of this work and pre-outage preparations.
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
I consider that, based on the evidence acquired during this intervention, that an inspection rating of Green is appropriate for LC 26 (Control and supervision of operations).