- Site: Hartlepool
- IR number: 19-155
- Date: January 2020
- LC numbers: 10, 22, 23, 24, 27, 28, 34
Executive summary
Purpose of Intervention
The main purpose of this intervention was to conduct a system-based inspection (SBI) of EDF Energy Nuclear Generation Ltd.’s (NGL) Hartlepool Power Station in relation to the boiler feed system. In addition, a Licence Condition (LC) 22 (‘Modification or Experiment on Existing Plant’) was also undertaken.
This intervention was undertaken as part of a series of planned interventions that are listed in the Hartlepool Integrated Intervention Strategy 2019/2020. The inspections were undertaken by the ONR nominated site inspector and three ONR nuclear specialist inspectors for structural integrity and probabilistic safety analysis (PSA), which for the purpose of this intervention report shall be referred to as “I”.
Interventions Carried Out by ONR
I performed a safety case informed SBI of the boiler feed system. Through examination of these systems, compliance inspections were performed against the following LCs:
- LC10 (Training);
- LC23 (Operating Rules);
- LC24 (Operating Instructions);
- LC27 (Safety Mechanisms and Devices);
- LC28 (Examination, Inspection, Maintenance and Testing); and
- LC34 (Leakage and Escape of Radioactive Material).
An LC22 inspection (Modification or Experiment on Existing Plant) was carried out by the site inspector.
The objective of the inspection was to determine whether the licensee’s arrangements were adequately implemented and in accordance with the systems’ safety case requirements. The boiler feed system is the source of the secondary coolant which provides a heat sink to the primary coolant. I chose to sample the Emergency Boiler Feed (EBF) system and High Pressure Back-Up Cooling System (HPBUCS).
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 the system based inspection, I judge that overall the boiler feed system meets the requirements of the safety case.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
System-Based Inspection
Based on the areas sampled during this system based inspection, I consider that Hartlepool has met its legal requirements that ensure that the boiler feed system is maintained and operated in accordance with the safety case and the station’s arrangements.
In summary, the outcome of the SBI of the system was as follows:
- I was satisfied, on the basis of my sample of a range of relevant staff, that Hartlepool has implemented its arrangements for training staff with responsibilities for the specific operation and maintenance of the system. I consider that, based on the evidence seen during this intervention, that an inspection rating of ‘Green – no formal action’ is appropriate for LC10.
- I was satisfied that the safety case limits and conditions have been identified and where necessary have been incorporated into technical specifications. I consider that, based on the evidence seen during this intervention, that an inspection rating of ‘Green – no formal action’ is appropriate for LC23.
- I was satisfied that operating instructions were in place to support plant operations. I consider that, based on the evidence seen during this intervention, that an inspection rating of ‘Green – no formal action’ is appropriate for LC24.
- I was satisfied that suitable and sufficient safety mechanisms, devices and circuits were connected and in working order with identified operating limits and conditions to meet the requirements of the safety case. I consider that, based on the evidence seen during this intervention, that an inspection rating of ‘Green – no formal action’ is appropriate for LC27.
- I also observed that, despite some minor shortfalls, the system was maintained appropriately meeting requirements of LC 28 and on that basis I have assigned a rating of ‘Green – no formal action’ against the LC28 element of this system based inspection.
- LC34 is applicable in a specific low frequency scenario for EBF related to a boiler tube leak in the re-heater section of the boiler. I was satisfied that adequate arrangements were in place for control of leakage and escape of radioactive material. I consider that, based on the evidence seen during this intervention, an inspection rating of ‘Green – no formal action’ is appropriate for LC34.
LC22 Compliance Inspection
Much of the NGL corporate arrangements and the ONR regulatory expectations were met with no significant shortfalls evident, therefore based on the sample inspected and the evidence obtained, I rate the inspection as ‘Green – no formal action’ for LC22 ‘Modification or Experiment on Existing Plant’, in line with established ONR guidance.
Despite that finding, there is evidence to suggest that personnel on the station need to take steps ensure a robust audit trail is always maintained. However, I concluded that the work associated with the ECs examined has been completed correctly and I was able to confirm this at a high level through a plant walkdown. There was also some further evidence to suggest that the scanning of WOCs (and associated checksheets) is still problematic. An existing regulatory issue in this area is already open and I will continue to press for improvements.
Conclusion of Intervention
After considering all the evidence examined during the inspections undertaken against LCs 10, 22, 23, 24, 27, 28 and 34, I judged that the requirements of the safety case have been adequately implemented at Hartlepool, with a rating of green assigned against licence conditions 10, 22, 23, 24, 27, 28 and 34.
Summary of findings
There were no findings from this inspection that could significantly undermine nuclear safety. At present, no additional regulatory action is needed over and above the planned interventions of Hartlepool power station as set out in the Integrated Intervention Strategy.