Heysahm 1 System Based Inspection(SBI 01) - Civil - Buildings, Site Infrastructure, Sea Defences and Flood Protection
- Site: Heysham 1
- IR number: 16-165
- Date: November 2016
- LC numbers: 10, 23, 24, 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 1 power station in line with the planned inspection programme contained in the Heysham 1 Integrated Intervention Strategy (IIS) for 2016/17.
Interventions Carried Out by ONR
The ONR nominated site inspector, together with a civil engineering specialist inspector and two further inspectors performed a system based inspection (SBI) of the civil buildings, site infrastructure, sea defences and flood protection 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
An inspector from EDF Energy Independent Nuclear Assurance also took part in this inspection.
Explanation of Judgement if Safety System Not Judged to be Adequate
From the areas sampled during this inspection, we judged that overall the civil buildings, site infrastructure, sea defences and flood protection 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 operation of the system. Based on the evidence sampled we concluded that personnel carrying out duties pertaining to the civil – buildings, site infrastructure, sea defences and flood protection system had received adequate training for their role or were being adequately mentored. 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 flooding safety case and the seismic monitors. We found the sampled operating instructions to be clearly laid out however we could not locate all the information we would expect to see regarding the detailed deployment of dam boards. An action has been placed on the station to address this shortfall. Notwithstanding this we considered that overall the instructions 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 the seismic monitoring equipment was functional and available. We inspected a sample of dam boards located around the site and found them to be available and in good condition. 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 maintenance requirements associated with the reactor building, cooling water pump house, sea defences, flood defences, site drainage and the trenches for essential services. 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 buildings and civil engineering structures are in an acceptable condition. We identified a number of areas where there are opportunities for improvement. The main area for improvement was in the way that defects were sentenced and managed and repairs progressed to timely completion. Actions have been placed on the station to address these shortfalls. Notwithstanding these shortfalls, overall compliance with LC 28 was considered to be acceptable and therefore an inspection rating of green was assigned.
- LC 34 (Leak and Escape of Radioactive Material and Radioactive Waste). We considered that Licence Condition 34 was not applicable to the sampled system components.
A single ONR level 4 issue has been raised to capture the actions identified in this intervention report. Satisfactory close-out of the issue will be monitored by the ONR nominated site inspector as part of routine regulatory business.
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 civil – buildings, site infrastructure, sea defences and flood protection system we judged that compliance with LC10, 23, 24, 27 and 28 met the expected standards and were rated as green. Overall we judged that the civil – buildings, site infrastructure, sea defences and flood protection system met the requirements of the safety case.
There are 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 1 power station as set out in the integrated intervention strategy, which will continue as planned.