- Site: Hinkley Point B
- IR number: 21-065
- Date: August 2021
- LC numbers: 10, 23, 24, 27, 28, 34
Executive summary
Purpose of Intervention
The purpose of this intervention was to undertake compliance inspections at EDF Energy Nuclear Generation Limited’s Hinkley Point B power station, in line with the planned inspection programme contained in Hinkley Point B’s Integrated Intervention Strategy (IIS) for 2021/22.
The intervention also consisted of a transport security inspection of the Bridgewater Railhead operations and arrangements.
Interventions Carried Out by ONR
This systems based inspection examined evidence to judge the duty holders compliance against six key Licence Conditions (LCs), selected to determine whether the safety case requirements of the system concerned are adequately implemented, and safety systems and structures are fit for purpose and will fulfil their safety functional requirements. The licence conditions assessed were: Licence Condition 10 (Training), Licence Condition 23 (Operating Rules), Licence Condition 24 (Operating Instructions), Licence Condition 27 (Safety Mechanisms, Devices and Circuits), Licence Condition 28 (Examination, Inspection, Maintenance and Testing) and License Condition 34 (Leakage and Escape of Radioactive Material and Radioactive Waste).
The transport security inspection was conducted as follow up and preparation for the increased rate of flask transport operations planned as part of defuelling operations at Hinkley Point B.
The system based inspection of system 09, Fuel Route systems was conducted by a mechanical engineering inspector and nuclear associate. The external transport route and railhead inspection was conducted by the nominated site inspector, and specialist inspectors for security and human and organisational capability. The inspection focussed on the fuel export route, in preparation for the stations transition to defuelling operations in 2022. The following fuel route systems were sampled:
- Fuel Storage Ponds
- Active Effluent Treatment Plant
- Flask Handling Facilities
- Fuel Export Route up to the Bridgewater Rail Head
Throughout this intervention record “I” refers to all the ONR Inspectors identified above.
The inspection comprised discussions with the licensee staff, a review of the licensee’s records, safety documentation and physical walkdown of plant areas on the station and on the external transport route.
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
Key Findings, Inspector's Opinions and Reasons for Judgements Made
From the areas sampled and the evidence I examined during this inspection; I consider that the licensee has adequately implemented the safety case claims relating to the Fuel Route Systems. I am content that the areas of the system I sampled are inspected, maintained, and operated in accordance with the safety case. I identified minor areas of improvement which I did not consider prejudice overall nuclear safety. The ratings I have assigned for each of the Licence Conditions are detailed below.
LC 10 (Training) – I examined the training records for individuals involved in the operation, maintenance, inspection and testing of the Fuel Storage Ponds and Flask Handling Crane. From my sample, I judged that the personnel undertaking and supervising these activities were suitably trained. I therefore assigned a rating of Green (No formal action) for License Condition 10 compliance.
LC 23 (Operating Rules) – I sampled limits and conditions identified in the safety case for the Fuel Storage Ponds and Active Effluent Treatment Plant. From the areas sampled, I considered the operating rules in the safety case were clearly identified, understood and compliance was demonstrated via appropriate surveillances.
From my sample, I judge that the Licensee has an adequate process in place for identifying and implementing the operating rules to demonstrate the safety and operation of the Fuel Export Route systems. I judged therefore, that a rating of Green (No formal action) is appropriate for this licence condition.
LC 24 (Operating Instructions) – I examined completed Operating Instructions used for carrying out shifty and weekly surveillance of limits and conditions important to the safety and operation of the Fuel Storage Ponds. I physically witnessed surveillances being carried out on a plant walk down of the Active Effluent Treatment Plant. I also sampled completed a work order card for interlock testing on the Flask Handling Crane. I confirmed that operations had been carried out as stipulated in the Operating Instructions. I consider that the Licensee has adequate arrangements in place for the production and implementation of Operating Instructions. I therefore judge that a rating of Green (no formal action) is appropriate for this licence condition, License Condition 24.
LC 27 (Safety Mechanisms, Devices and Circuits) – I reviewed the maintenance and test records associated with safety mechanisms on the Flask Handling Crane and Fuel Storage Ponds. I physically walked down the Active Effluent Treatment Plant and Flask Handling Crane areas. I consider the licensee adequately demonstrated that Safety Devices Mechanisms and Circuits were connected and in good working order. The key safety mechanisms devices and circuits were clearly identified, and adequate periodic inspection and testing to confirm plant condition and availability was being undertaken in accordance with the licensee’s arrangements. I judged therefore, that a rating of Green (No formal action) was appropriate for License Condition 27.
LC 28 (Examination, Inspection, Maintenance and Testing) – I sampled the licensee’s maintenance arrangements through reviewing records and discussions with the system engineer. I sampled completed work order cards and the associated maintenance and inspection procedures identified on the plant maintenance schedule for calibration and functional testing of safety significant equipment. I confirmed that the licensee’s requirements were being implemented adequately.
Overall, I judge that the licensee is undertaking examination, inspection, maintenance and testing in accordance with the specified arrangements and frequencies. I am content that the evidence sampled demonstrated adequate implementation of arrangements. Therefore, I judge that a rating of Green (no formal action) to be appropriate for licence condition 28.
LC 34 (Leakage and Escape of Radioactive Material and Radioactive Waste) – I sampled the Active Effluent Treatment Plant to ensure there was adequate control and containment of radioactive matter. From discussions with the licensee, sampling of process flow diagrams and review of evidence of appropriate monitoring of radioactive waste discharge, I am content that the licensee has adequate arrangements for monitoring the leakage and escape of radioactive material. I judge that a rating of Green (no formal action) to be appropriate for licence condition 34.
Conclusion of Intervention
Based on my sample, I judge that the Fuel Export Route (System 09) met the requirements of the safety case, with areas for improvement noted. The inspection findings were shared and accepted by the licensee during the feedback session. I shared regulatory observations and recommendations with the licensee which will be followed up by the nominated site inspector as part of normal regulatory business.
I judge the licensee adequately demonstrated ownership and implementation of its safety case. In addition, it demonstrated an adequate understanding of its arrangements to ensure and maintain the safety of its Fuel Route systems.