Dungeness B (EDF Energy) - Irradiated Fuel Dismantling Facility (SBI 16)
- Site: Dungeness B
- IR number: 17-187
- Date: December 2017
- LC numbers: 10, 23, 24, 27, 28, 34
Purpose of Intervention
The purpose of this intervention is to undertake a system based inspection (SBI) of the Irradiated Fuel Dismantling Facility (IFDF) at EDF Energy Nuclear Generation Ltd's (NGL's) Dungeness B nuclear power station. The inspection was conducted in line with the inspection programme contained in the Dungeness B Integrated Intervention Strategy (IIS) for 2017/18.
Interventions Carried Out by ONR
SBI of IFDF
The intervention was conducted by mechanical and structural integrity specialist inspectors. The intervention was conducted to establish that the basic elements of the IFDF safety case as implemented through its Structures, Systems and Components (SSCs) important to safety are fit for purpose and that they fulfil and will continue to fulfil their safety functional requirements. This was undertaken through examination of six 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
This intervention was conducted by a mechanical engineering specialist inspector. The intervention was to establish Dungeness B Nuclear Power Stations compliance with the requirements of the LOLER regulations.
The intervention was based on sampling the implementation of the arrangements in place ensuring their adequacy in relation to the IFDF and LOLER compliance.
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 our inspection, we judged that overall, the IFDF system met the requirements of the safety case and is adequate.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
SBI of IFDF:
- LC 10 (Training) - We examined the role profile and training records of a number of personnel involved in operations and maintenance activities associated with the IFDF. We judged that the personnel undertaking the operations and maintenance activities were suitably qualified and experienced. We therefore assigned a rating of Green for LC 10 compliance.
- LC 23 (Operating Rules) - The technical specifications adequately specified the limits and conditions of operation (LCO) reflecting those specified in the living safety case. In addition, the surveillance records and compliance check sheets demonstrated that the technical specifications were implemented as appropriate during IFDF activities. We therefore assigned a rating of Green for LC 23.
- LC 24 (Operating Instructions) - We examined a number of station operating instructions and maintenance instructions. Overall, we considered that these documents provided adequate instructions to enable suitably qualified and experienced staff to complete tasks safely. We noted some minor opportunities improve the quality of some maintenance instructions sampled. These will be addressed via the station's on-going programme to enhance maintenance instruction quality. We therefore assigned a rating of Green for LC 24.
- LC 27 (Safety Mechanisms, Devices and Circuits) - We examined and confirmed that the CO2 and cooling safety systems relevant to the IFDF were adequately maintained and tested on a regular basis. We judged that a rating of Green was appropriate for LC 27.
- LC 28 (Examination, Inspection, Maintenance and Testing) - We examined a number of maintenance schedule items and work order cards. We confirmed that the periodicity of maintenance activities was appropriate and judged that the IFDF was being adequately maintained. We therefore assigned an IIS rating of Green to this LC 28.
- LC 34 (Leakage and Escape of Radioactive Material and Radioactive Waste) - We examined the maintenance regime for the IFDFs ventilation filters and judged this to be adequate. We therefore assigned an IIS rating of Green (to this LC 34.
- I examined the licensee's arrangements for managing lifting activities and concluded that they followed the corporate arrangements. These are designed to provide a means of ensuring consistent implementation of the LOLER regulations. I therefore judged that overall compliance with the LOLER regulations was adequate.
Conclusion of Intervention
After considering all of the evidence presented by the licensee we concluded that the arrangements and their implementation, associated with the IFDF met the requirements of the safety case and were adequate. An IIS rating of Green is considered to be appropriate for the system based inspection and no regulatory issues were raised.
With respect to the LOLER themed compliance inspection, I consider, after examining the licensees arrangements sampled I concluded that these met the requirements of the LOLER regulations. An IIS rating of Green was considered appropriate for this aspect of the inspection.
There were no findings from the interventions that could significantly undermine nuclear safety.