Hinkley Point B - Planned intervention
- Site: Hinkley Point B
- IR number: 15-013
- Date: May 2015
- LC numbers: 4, 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 Civil Nuclear Reactor Programme (CNRP) 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) and a specialist ONR fuels inspector:
- Carried out a system based inspection on fuel assemblies.
- Carried out a licence condition 4 (restrictions on nuclear matter on the site) compliance inspection.
- Discussed key matters with the site internal regulator.
- Carried out further initial enquiries into a recent event involving the ejection of a closure unit from the buffer store.
- Held a number of information exchange meetings with station staff.
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 – the system was judged to be adequate.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
From the system based inspection on fuel assemblies we concluded that:
- For LC 10 (training): we judged that the licensee was providing an adequate level of criticality awareness training to all station staff (including contractors) and that for persons working in areas under criticality control, a suitably enhanced level of training was provided. We judged the LC10 element of the inspection warranted an IIS rating of 3, adequate.
- LC 23 (Operating Rules): the licensee’s Operating Rules (OR) were adequately defined within the Technical Specifications (TS). We reviewed compliance with the TS, via sampling of a randomly chosen sample of recent fuel build records and found that they were all in order. We judged the LC23 element of the inspection warranted an IIS rating of 3, adequate.
- LC 24 (Operating Instructions): we sampled compliance with the lower level instructions (eg Station Operating Instructions) and found that the instructions had been adhered to and signed off as required. We judged the LC24 element of the inspection warranted an IIS rating of 3, adequate.
- LC 27 (Safety Mechanisms, Devices and Circuits). We judged that the gamma detectors and interlocks on the doors to the New Fuel Cell provided a safety function as they provided protection to the operators from potential high radiation exposures in the cell. We examined the maintenance requirements and records and found them to be in order. We judged the LC27 element of the inspection warranted an IIS rating of 3, adequate.
- LC 28 (Examination, Inspection, Maintenance and Testing): Generally the maintenance records we sampled were in good order, although we did identify some areas for improvement. Overall we judged the LC28 element of the inspection warranted an IIS rating of 3, adequate.
- LC 34 (Leakage and Escape of Radioactive Material and Radioactive Waste): we found the station’s Burst Can Detection (BCD) equipment to be in good order. Some areas for improvement were noted on the Gaseous Activity Monitoring system and this system is scheduled for refurbishment in the near future. In the interim we accepted the licensee’s position that the BCD system could act as a fall-back, along with gas bottle sampling. The licensee accepted that it needs to review the As Low as Reasonably Practicable (ALARP) justification for the off-site analysis of gas bottle samples. We judged the LC34 element of the inspection warranted an IIS rating of 3, adequate.
Overall, we concluded that the arrangements and their implementation associated with fuel assemblies met the requirements of the safety case and was deemed to be adequate.
For licence condition 4 (restriction on nuclear matter on the site) we concluded that the site was following its procedures for controlling nuclear matter on the site including safety cases, procedures, dedicated facilities and records management. We therefore assigned an IIS rating of 3, (adequate) to this inspection.
I was unable to meet face to face with the site internal regulator (Independent Nuclear Assurance – INA) on this occasion but did discuss progress with key issues on site via telephone. I will meet with INA whilst next on site.
A significant near miss event occurred on the pile cap when an outage closure plug was ejected from a buffer storage tube. There were no nuclear safety implications or damage to the plant, no fuel was involved and nobody was injured (although operators were in the immediate vicinity). ONR carried out initial enquiries to determine what happened and what action had been/is being taken by the licensee.
I was satisfied with the information exchanged during meetings with station staff on a range of topics including recent Safety Rules events, plant configuration control, compliance with pressure system safety regulations, issues on Reactor 3 including standpipe temperatures, generator transformer 7 and progress with the significant safety case developments.
Conclusion of Intervention
There are no findings from this inspection that could significantly undermine nuclear safety.