Office for Nuclear Regulation

This website uses non-intrusive cookies to improve your user experience. You can visit our cookie privacy page for more information.

Conventional health and safety visit - Sellafield

Executive summary

Purpose of intervention

Plant visits and meetings to establish progress of Sellafield Ltd.’s arrangements for managing conventional health and safety (CHS), including legionella risk systems, CHS matters in the main engineering facility, and workplace transport safety.

One of the purposes conferred on ONR by the Energy Act 2013 is the regulation of nuclear site health and safety. The ONR CHS team contributes to this purpose by providing specialist conventional health and safety regulatory support and advice to other ONR regulatory programmes. This intervention forms part of a programme of work underway by the ONR Conventional Health & Safety (CHS) team to secure improvements in conventional health and safety management within the nuclear industry.

Interventions Carried Out by ONR

The key regulatory activities undertaken during the three day visit were based around:

This intervention enabled ONR to verify progress by Sellafield Ltd. for a number of elements of CHS management rather than being a detailed inspection of one particular CHS topic across the Sellafield Ltd. organisation. The plant visits were planned in order to provide an opportunity to verify action taken by Sellafield Ltd to resolve or progress concerns previously highlighted by ONR regarding CHS management in the Engineering facility and management of the HALES and Evaporator D cooling systems as legionella risk systems. ONR has four related regulatory issues open; issue numbers 4448 (CHS management), 4006 (HALES), 2723 (road/rail interfaces), and 4897 (Engineering Facility).

Regulatory judgement was based on determining compliance with sections 2 & 3 of the Health & Safety at Work etc Act 1974 and a number of relevant statutory provisions made under the Act.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

Key findings, inspector opinion and reasons for judgements made regarding the ONR enquiries into the management of the HALES cooling system as a legionella risk system are not included in this record as the enquiries are ongoing.

The findings, inspector opinion developed and judgements made during the plant visits to the Main Engineering facility and Evaporator D were made using the relevant legislation, Approved Code of Practices or well established guidance as benchmark standards.

As per previous visits to the Main Engineering facility, it was evident that progress was being made to improve CHS management standards in the facility. However, the facility still has a significant amount of work to undertake in order to attain the standards expected of a large engineering facility. For example, ONR were informed that exposure monitoring of ‘stick’ stainless steel welding is yet to take place, to confirm whether existing engineering controls deliver the required reduction in exposure to welding fume.

Conversely, benchmarking against other engineering facilities has been undertaken and there is evidence that the relevant management personnel are now providing the necessary oversight. This appears to be resulting in visible improvements.

The Evaporator D cooling system plant inspection (from a legionella risk management perspective) was undertaken following discussions with the ONR inspector regulating the Evaporator D project and the Sellafield HALES managers that will take responsibility for Evaporator D later in 2017.

ONR was informed that the Evaporator D cooling system has been designed such that chlorine based chemicals can be used for water treatment purposes if required. In addition, the cooling tower was observed to be in a good standard of cleanliness although some mild steel components were seen that could corrode within the tower, providing a nutrient source for legionella. Sellafield confirmed these would be addressed during the next tower outage.

A review of the relevant documentation presented as the arrangements for managing legionella risks associated with the system was undertaken prior to the plant visit. This showed that the documented arrangements require revision to ensure proportionate adherence to the relevant aspects of the Legionella Approved Code of Practice.

In addition, a large number of dead legs have recently been identified within the cooling system. Some of the dead legs were introduced as part of works to design seismic capability within the cooling system. The volume of some of the dead legs is large. Sellafield is in the process of determining whether the identified dead legs are manageable within the current arrangements and the nature and extent of any further action that may be required.

Conclusion of Intervention

Initial feedback was provided at the end of each meeting and plant visit to the relevant Sellafield personnel.

Regarding the HALES cooling tower - Detailed conclusions are not included in this record, as further enquiries and regulatory activities are continuing.

The nature of the plant visits undertaken was such that whilst regulatory judgement was applied during the plant visits, inspection ratings have not been determined.

The Main Engineering facility still has a significant amount of work to undertake in order to attain the standards expected of a large engineering facility. However, evident progress is now being made to improve CHS management standards in the facility. A further ONR visit will be arranged for Q3 2017/18 to ensure all relevant actions have been completed.

It was evident from the Evaporator D plant visit that the Evaporator D system is being proactively managed and monitored as a legionella risk system. It is also clear that the relevant Sellafield personnel have a good awareness of legionella risks and how these may apply to the Evaporator D cooling system. However, a further ONR visit is required (provisionally in July 2017) to ascertain whether the management arrangements are sufficient once the full extent of the risk presented by dead legs within the cooling system is known.