Heysham 2 - SBI01 and LC6 Inspection
- Site: Heysham 2
- IR number: 18-008
- Date: April 2018
- LC numbers: 6, 10, 23, 24, 27, 28, 34
Purpose of Intervention
The purpose of this intervention was to carry out a system based inspection at EDF Energy Nuclear Generation Limited’s (NGL’s) Heysham 2 power station in line with the planned inspection programme contained in the Heysham 2 Integrated Intervention Strategy (IIS) for 2018/19.
Interventions Carried out by ONR
A civil engineering specialist inspector, assisted by the Heysham 2 nominated site inspector and two external hazards specialist inspectors performed a system based inspection (SBI) of the sea defences, flood protection and drainage system to judge the system performance against its safety function. Through examination of this system and associated sub-systems, we performed compliance inspections against the following Licence Conditions (LCs):
- LC 10 - Training
- LC 23 - Operating rules
- LC 24 - Operating instructions
- LC 27 - Safety mechanisms, devices and circuits
- LC 28 - Examination, inspection, maintenance and testing
- LC 34 - Leakage and escape of radioactive material and radioactive waste
I, the nominated site inspector undertook an LC6 compliance inspection which involved the consideration of both generic and local implementation documents as defined within the licensee’s arrangements. The following areas were covered as part of the inspection:
- Record schedule and routine reviews management process overview
- Sample from the record schedule & routine reviews
- Arrangements for the tracking of ONR issues and their progress
- Sample of drawing register
During the visit the nominated inspector held discussions with the station director and with the licensee’s internal safety regulator.
During the inspection week, the Heysham 1 and 2 nominated site inspectors attended the Emergency Preparedness Consultative Committee (EPCC) which was held at the Lancaster Police headquarters. During the meeting the ONR inspectors provided an overview of each stations’ performance for the recent Level 1 exercises and shift exercises and of recent organisational changes within ONR.
Explanation of Judgement if Safety System not judged to be Adequate
From the areas sampled during this inspection, we judged that overall the sea defences flood protection and drainage system met the requirements of the safety case.
Key findings, Inspector's Opinions and Reasons for Judgements Made
With respect to the system based inspection the following judgements were made;
- LC 10 (Training) - We examined the training records for a sample of the personnel involved in the inspection of the system. We found that essential training was generally within date however we did identify two elements of essential training relevant to sea wall inspection that were flagged as potentially not being in ticket. In light of this minor anomaly an ONR regulatory issue has been raised for the training deportment to provide clarity of the SQEP status for the individual concerned. Notwithstanding this point, we judged that compliance with LC 10 met ONR’s expectations and hence assigned an inspection rating of Green.
- LC 23 (Operating Rules) and LC 24 (Operating Instructions) - Based on the evidence sampled we concluded that suitable limits and conditions had been derived from the safety case, and are implemented through the technical specifications (operating rules) and station operating instructions. We were satisfied that suitable arrangements were in place to control the availability of systems structures and components qualified against external hazards and specifically, the flood defences claimed in the external flooding safety case. We found that the sampled operating instructions clearly identified the operator actions to be taken following warnings of significant storm or flood and were adequate. We judged that compliance with LC 23 and LC 24 was consistent with ONR’s expectations and hence assigned an inspection rating of Green to both licence conditions.
- LC 27 (Safety Mechanisms, Devices and Circuits) - We sampled devices identified in the station’s maintenance schedule against safety case requirements. We confirmed that adequate checks were carried out to ensure that the Quadrant Excess Drainage pumps were functional and available. We therefore considered that compliance with LC 27 met ONR’s expectations and hence assigned an inspection rating of Green.
- LC 28 (Examination, Inspection, Maintenance and Testing) - We sampled the inspection and maintenance requirements associated with the sea defences, drainage, Quadrant Excess Drainage pumps and secondary containment of the Active Effluent Treatment Plant. Based on the evidence sampled and the plant walk-down we considered that inspections were being undertaken in line with the requirements of the maintenance schedule and that overall the system is in an acceptable condition. Although we did not identify any immediate threat to the integrity of the sea defences, we observed a number of areas where the condition of the structures can be improved. We were content that the station is aware of the defects in the structure and that significant investment is planned to address them. Overall, compliance with LC 28 was considered acceptable and therefore an inspection rating of Green was assigned.
- LC 34 (Leak and Escape of Radioactive Material and Radioactive Waste) - We considered that the safety case does not make any claims on essential operator actions required for the radioactive waste activities that could be threatened by external flooding. We therefore sampled the mitigation measures contained in station operating instructions following receipt of a warning of significant storm or flood and the examination, inspection, maintenance and testing activities required to ensure that the risk of mobilisation of active waste due to flooding is as low as reasonably practicable. We considered that compliance with LC 34 met ONR’s expectations and hence assigned an inspection rating of Green.
In carrying out our inspection against LC 27 we observed a shortfall in compliance against LC 22 (Modification or experiment on existing plant) relating to the failure of the licensee to update documentation relating to the Quadrant Excess Drainage pumps following production of an Engineering Change. In response to our finding, the licensee raised a Condition Report to update the relevant documentation. As this type of shortfall forms part of a current intervention by the licensee’s Independent Nuclear Assurance team, we were content for the ONR nominated site inspector to follow up progress with this matter as part of routine regulatory business.
The LC6 inspection identified areas of good practice; however, the inspection also identified two areas where the licensee’s arrangements had minor shortfalls. I have therefore elected to raise two ONR regulatory issues in order to monitor the licensee’s progress of them. Notwithstanding these two minor shortfalls, I considered that, based on the evidence sampled for this compliance inspection, compliance with LC 6 met ONR’s expectations and hence assigned an inspection rating of Green
The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.
Conclusion of Intervention
Following the system based inspection of the, sea defences, flood protection and drainage system we judged that compliance with LC10, 23, 24, 27, 28 and 34 met the expected standards and were rated as Green. A single ONR issue has been raised relating to the training which will be followed up by the site inspector. Overall, we judged that the sea defences, flood protection and drainage system met the requirements of the safety case.
Following the LC 6 Compliance inspection, two ONR issues were raised in order for the site inspector to follow the licensee’s progress of them. Notwithstanding these two minor shortfalls, the nominated site inspector judged that compliance with LC6 met ONR’s expectations and hence assigned an inspection rating of Green.
As A result of ONR inspections 3 ONR issues have been raised in order to monitor the licensee’s progress of them.
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 Heysham 2 power station as set out in the integrated intervention strategy, which will continue as planned.