Office for Nuclear Regulation

Systems Based Inspection 3 - Boiler Feed and other planned site inspection

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:

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:

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.