Hinkley Point B - SBI17 Gas Circulators
- Site: Hinkley Point B
- IR number: 17-097
- Date: August 2017
- LC numbers: 10, 23, 24, 27, 28, 34
Purpose of Intervention
This was a planned inspection of EDF Energy Nuclear Generation Ltd’s (NGL’s) Hinkley Point B power station, undertaken as part of the planned intervention strategy for the Operating Facilities Division (OFD) of the Office for Nuclear Regulation (ONR).
The work was carried out in line with the planned inspection programme contained in the Hinkley Point B Integrated Intervention Strategy (IIS).
Interventions Carried Out by ONR
I (the nominated site inspector for Hinkley Point B undertook a System Based Inspection (SBI) on the gas circulators, supported by an ONR Mechanical Engineering specialist Inspector.
In addition to the SBI, the nominated Site Inspector also:
- Carried out activities in support of the fall from height investigation.
- Attended the feedback session post the Security Contingency Plan (SCP) demonstration exercise.
- Met with the Technical and Safety Support Manager
- Met with the Station Director.
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
From this inspection, I judge that the gas circulators met the requirements of the safety case.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
From the system based inspection on gas circulators, I concluded that:
- In relation to the LC 10 (training) element of the SBI, based on the sampling undertaken, I was satisfied that the personnel I sampled were SQEP to perform the witnessed GC maintenance activity. However, I was not content that the associated training arrangements were adequately implemented in compliance with the licensee’s own arrangements. The licensee has raised a condition report to address the ONR findings and has undertaken an extent of condition review. I have therefore raised an ONR regulatory issue to monitor the licensee’s progress; I therefore judged an IIS rating of Amber for the LC10 element of this inspection is appropriate.
- In relation to the LC 23 (operating rules) element of the SBI, I considered that NGL demonstrated a good understanding of the requirements of the safety case. I judged that the supporting technical specifications, commentaries, and schedules were consistent with the claims presented within the living safety case document and system based view. I concluded that the LC 23 element of this inspection warranted an IIS rating of Green.
- In relation to the LC 24 (operating instructions) element of the SBI, I was satisfied that the operating instructions provided sufficient detail, and captured the requirements of the safety case. I concluded that the LC 24 element of this inspection warranted an IIS rating of Green.
- In relation to the LC 27 (safety mechanisms) element of the SBI, I was satisfied that the availability and reliability of the safety mechanism, devices and circuits for the gas circulator systems identified in the safety case were demonstrably available and in good working order. I concluded that the LC 27 element of this inspection warranted an IIS rating of Green.
- In relation to the LC 28 (examination, inspection, maintenance and testing) element of the SBI, I considered that the licensee had demonstrated that its processes and procedures in for the examination, inspection, maintenance and testing of the gas circulators met legal requirements, I therefore concluded that the gas circulator arrangements under LC 28 warranted an IIS rating of Green.
- In relation to the LC 34 (leakage and escape of radioactive material) element of the SBI, I considered the leak management arrangements for the gas circulator oil cooling pumps sump and concluded that this was adequately managed. During the LC 34 compliance inspection, I examined elements of the company licence compliance arrangements and sampled the stations LC34 leak schedule of radioactive leaks which is used to sentence leaks with a work request prioritisation. I was satisfied that the station has implemented its compliance arrangements and therefore I consider compliance with LC34 to be met and have given an IIS rating of Green.
Conclusion of Intervention
After considering the evidence presented against, LC23, 24, 27, 28 and 34, I concluded that the licensee complied with its legal duties regarding the gas circulator systems inspected and met the requirements of the safety case and in line with ONR’s Inspection Rating Guide, a rating of Green has been assigned
However in relation to compliance against LC10, I judged that an IIS rating of Amber was proportionate based on the sample observed on the day.
There are no findings from this inspection that could significantly undermine nuclear safety.