The purpose of this intervention was to carry out a System Based Inspection (SBI) of the sea defences, flood protection and drainage system at EDF Energy Nuclear Generation Limited’s (NGL) Torness power station.
The intervention was planned in accordance with ONR’s Integrated Intervention Strategy (IIS) for Torness of 2019/20.
The ONR external hazards and civil engineering 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):-
The licensee’s internal safety regulator also took part in this intervention.
The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.
Recorded separately (Section 2.1 of this report) , the nominated site inspector carried out a series of routine engagements with the Station to gather intelligence, share views and discuss progress with existing regulatory issues. This included a visit from ONR’s Deputy Chief Inspector, discussion of shift alignment and attendance at the emergency arrangements review meeting.
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.
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 Fuel Route. We found that there were arrangements to ensure that individuals remain ‘in ticket’ for training and these are being adequately implemented. Of those training records sampled, we found that essential training was within date. We discussed training requirements for the SQEP role of Station Civil Engineer and considered that the role is clearly defined and suitable. We also discussed the Hazards Awareness Training course which was piloted at Torness and considered that this has been positively received by the station. The site provided us with guidance on how to roll out the training across the fleet, which we will discuss with the relevant Design Authority staff. Overall we judged that compliance with LC 10 met ONR’s expectations and hence assigned an inspection rating of Green, in accordance with ONR RAG rating system (ONR-INSP-GD-064 rev 3).
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 considered that these were adequate. We also found that the sampled operating instructions clearly identified the operator actions to be taken following a seismic event with the potential to cause failure of the flood defences. 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. Refer to ONR-INSP-GD-064 rev 3.
LC 27 (Safety mechanisms, devices and circuits): Based on the evidence sampled we concluded that adequate arrangements for safety mechanisms, devices and circuits had been made and implemented via the LC28 MITS arrangements. The licensee does not classify any of the sampled systems as SMDCs in accordance with LC27. However, this is partly a matter of terminology, and for practical purposes the licensees arrangements treat the Pond water level probe as an SMDC. In the case of the other systems sampled there are adequate justifications for not treating them as SMDCs. We judged that for the sample inspected the LC27 arrangements are adequate and hence assigned an inspection rating of Green for this licence condition. Refer to ONR-INSP-GD-064 rev 3.
LC 28 (Examination, inspection, maintenance and testing): Based on the evidence sampled we concluded that adequate arrangements for examination, inspection, maintenance and testing had been made and that there had been regular and systematic application of these. We considered the arrangements for a site asset management system, noting the ‘Passport System’ contained on the NGL Controlled Document Management System (CDMS) which we were informed included all nuclear significant structures. We noted that the inspection requirements were informed by the safety case for the SSC’s considered and included in the Maintenance, Inspection and Test Schedule (MITS). We considered the “compliance coordinator” role in ensuring the SQEP requirements of the staff involved in the inspections were specified and met.
We noted a number of inspection control and monitoring systems including “FLAIR” and “SHIP” employed at Torness.
We judged that compliance with LC 28 was consistent with ONR’s expectations and hence assigned an inspection rating of Green. Refer to ONR-INSP-GD-064 rev 3.
LC 34 (Leakage and escape of radioactive material and radioactive waste): Based on the evidence sampled we concluded that radioactive material and radioactive waste on the site was being adequately contained and controlled. We further concluded that radioactive leakage or escape would be detectable and considered the arrangements for notification, recording, investigation and reporting to be adequate. We judged that compliance with LC34 was in compliance with ONR expectations and hence assigned an inspection rating of Green. Refer to ONR-INSP-GD-064 Rev 3for ONR RAG rating system and ONR Technical Inspection Guide, NS-INSP-GD-34 re the introduction of Environmental Authorisation (Scotland) Regulations 2018.
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 in accordance with ONR RAG rating system(ONR-INSP-GD-064 Rev 3). Overall, we judged that the sea defences, flood protection and drainage system met the requirements of the safety case.
There are no findings from this intervention that could significantly undermine nuclear safety at Torness. At present, no additional regulatory action is needed over and above the planned interventions of Torness as set out in the Integrated Intervention Strategy, which will continue as planned.