Sizewell B - LC Compliance Inspection
- Site: Sizewell B
- IR number: 18-019
- Date: May 2018
- LC numbers: 7, 10, 23, 24
Purpose of Intervention
The purpose of this intervention was to undertake licence condition (LC) compliance inspections at EDF Energy Nuclear Generation Limited’s (NGL) Sizewell B Power Station, in line with the ONR’s Operational Facilities Division intervention strategy. The intervention was carried out by the ONR site inspector, supported by a number of specialist ONR inspectors.
Interventions Carried Out by ONR
The intervention was aimed at evaluating the control of Reactor Coolant System (RCS) and main feedwater chemistry at Sizewell B. The inspection team also conducted an intervention to examine organisational learning at Sizewell B, focusing on the station’s response to lessons learned following to a fall from height at Hinkley Point B power station last year and an evaluation of the quality of internal investigations undertaken by the licensee to identify causes of incidents initiated in reports undertaken. During these interventions, inspections were performed against the following Licence Conditions (LC) which are applicable provisions of the Energy Act 2013:
- LC7 - Incidents on site
- LC10 - Training
- LC23 - Operating Rules
- LC24 - Operating Instructions
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
Not applicable during this intervention.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
- LC7 (Incidents on site) - Based on a sample inspection I judge that Sizewell B has appropriately responded to lessons from the HPB fall from height identified with Mandatory Evaluation report (MEVL). Application of the MEVL process at Sizewell B has resulted in improvement of Sizewell B’s roof register and its visibility to personnel permanently on site. I am also content that the MEVL has resulted in the installation of engineered protection around fragile surfaces, where the licensee considers this reasonably practicable. I am also satisfied that overall, incidents which are targeted for an apparent cause investigation are subject to an appropriate standard of investigation consistent with NGL’s LC7 arrangements. A minor shortfall was noted regarding the omission of roofs accessed by staff under NGL’s general hazards arrangements, from the area risk assessment process. NGL have committed to address minor shortfall which will be monitored via in entry on the ONR issues database. Based on the results of my sample inspection, I judge that that NGL met its legal requirements under licence condition 7. I consider the following inspection rating appropriate: GREEN.
- LC10 (Training) - NGL were able to demonstrate appropriate training records for newer members to the chemistry team, with proactive management of singleton SQEP resources and training packages sampled for infrequent start-up and shut down operations as discussed under LC24 (see below). I consider the following inspection rating appropriate: GREEN.
- LC23 (Operating Rules) - Appropriate operating rules were identified for chemistry for both the Reactor Coolant System (RCS) and main feedwater systems. However, some inconsistences were identified for chemistry operating rules and sampling frequencies for the RCS. A regulatory issue has therefore been raised to track the station’s progress in resolving the minor inconstancies. Notwithstanding this issue, I consider the following inspection rating appropriate: GREEN.
- LC24 (Operating Instructions) - NGL demonstrated that appropriate hold points and inclusion of chemistry operating rules in start-up and shut down transients. Importantly, these also included important operating rules identified under LC 23 discussions (see above). Positively, operating instructions for chemistry took account of OPEX from previous outages. I consider the following inspection rating appropriate: GREEN.
- More generally related to chemistry, the potential for zinc injection at SZB was discussed. Positively, station is proactively considering the benefits of zinc injection to existing reactor coolant dosing regime and was able to demonstrate OPEX gathered from other PWRs to support this. A regulatory issue has been raised to enable ONR to maintain oversight of this work and track progress.
Conclusion of Intervention
There are no findings from this inspection that could significantly undermine nuclear safety. No change is necessary to the planned interventions and inspections for 2018-19 at SZB as a result.