Executive summary
Date(s) of inspection: February 2024
Aim of inspection
Confirm that the boiler feed system (sampled parts of the overall system) is able to meet the nuclear safety functional requirements defined in the station’s Safety Case.
Subject(s) of inspection
- LC10 - Training - Rating: Green
- LC23 - Operating rules - Rating: Green
- LC24 - Operating instructions - Rating: Green
- LC27 - Safety mechanisms, devices and circuits - Rating: Green
- LC28 - Examination, inspection, maintenance and testing - Rating: Green
- LC34 - Leakage and escape of radioactive material and radioactive waste - Rating: Not Rated
- Overall Inspection Rating - Rating: Green
Key findings, inspector's opinions and reasons for judgement made
Over a two day inspection, I sampled significant (high safety) systems and components within the boiler feed system, the focus of the inspection was the decay heat system and the make-up water treatment plant, in particular, the chemical ingress protection system.
Across the licence conditions relevant for this inspection (10, 23, 24, 27 and 28), the licensee demonstrated a good level of compliance. LC34 was not deemed applicable or relevant for this inspection and therefore not rated.
Of particular note, Heysham 2 staff were able to provide a robust strategy for dealing with obsolescence issues related to their chemical ingress protection system, evidence of this which was witnessed whilst inspecting the site.
In terms of plant condition, noting the above, the make-up water treatment plant suffers from active degradation, which is made more complex given obsolescence issues on control equipment. There were areas of notable degradation during the walk down but also areas of investment and improvement. This is similar for some aspects of the decay heat system (and emergency boiler feed system) but in contrary some aspects, e.g. the pumps, remain dormant during operation and are segregated so plant condition is generally good and remains unchanged since I last inspected several years previous. I was satisfied from my samples that the staff are appropriately managing these systems and components through operations and maintenance which aligned with their safety case.
Conclusion
Overall, the licensee demonstrated adequate implementation of the safety case across a number of areas of the boiler feed system, in particular our focus areas, the decay heat boiler system and the chemical ingress protection system (several sets spread across the water treatment plant). Based on my sample, I have rated the inspection green against the licence conditions (10, 23, 24, 27 and 28) for the system.