Office for Nuclear Regulation

AWE Aldermaston – Inspection ID: 51974

Executive summary

  • Inspection date(s): 12/10/2022

Purpose of inspection

The purpose of the intervention was for the ONR to inspect and determine the adequacy of implementation of AWE’s formal arrangements for compliance with LC 11 via an on-site demonstration of their emergency arrangements during a Level 1 exercise.

Subject(s) of inspection

The following actives were the subject of this inspection:

  • LC11 – Emergency arrangements – Rating – Green

Key findings

The Office for Nuclear Regulation (ONR) undertakes all regulatory interventions with the Aldermaston nuclear site licensee, AWE plc (AWE) against a strategy defined by the ONR Weapons sub-Division. In accordance with that strategy, a Licence Condition (LC) 11 compliance inspection was undertaken at Aldermaston, as planned, on 12 October.

The purpose of the intervention was for the ONR to inspect and determine the adequacy of implementation of AWE’s formal arrangements for compliance with LC11 via an on-site demonstration of their emergency arrangements during a Level 1 exercise. Other meetings were also undertaken and covered in this report as part of ONR’s routine interventions.

The intervention focused on the people and processes that AWE has in place to comply with its LC11 arrangements and was undertaken via the assessment of the on-site Level 1 exercise.

The intervention was undertaken and rated against published guidance on ONR’s expectations, as described in the technical inspection guides (TIGs), which can be found at Office for Nuclear Regulation (ONR) Compliance inspection – Technical inspection guides. Specifically, this included NS-INSP-GD-011 and ONR-INSP-GD-064.

Based on the evidence sampled at the time of the intervention against AWE’s LC11 arrangements and ONR’s associated LC requirements and TIGs, I consider that AWE has consistently implemented its arrangements across the functions sampled. This current view aligns with that of AWE’s own LC owner and the internal regulator findings. I was satisfied that the exercise scenario was realistic and sufficiently challenging.

It is my opinion that the Level 1 emergency response demonstration exercise provided adequate evidence of implementation of the established emergency arrangements within the Uranium Technology Centre, the Medical Evacuation Centre and the Aldermaston Emergency Operations Control Centre, in respect of LC11. A Green rating is therefore considered appropriate, in accordance with ONR Guide ONR-INSP-GD-064. I will write to AWE to reflect this judgement and include all observations from the demonstration exercise to assist with a programme of continuous improvement.

The planned interventions set out in the Operating Facilities Division Weapons Sub-Division Strategy for Aldermaston site remain valid and will be followed for future inspections.

Judgements made

The team of ONR inspectors made observations at various locations during the exercise. The Defence Nuclear Safety Regulator (DNSR) also assessed the exercise demonstration and provided additional evidence/observations, consistent with the approach of joined up regulation. The prioritised observations were fed back to AWE as part of the “hot wash-up” meeting. I was encouraged that many of AWE observations at the hot wash-up meeting aligned with ONR/DNSR’s, which provided assurance of AWE’s open, honest and self-challenging approach to the exercise demonstration. Whilst there are a number of opportunities for learning that were highlighted from the exercise, this is indicative of the challenging scenario AWE set themselves, is an important aspect of the exercise demonstration from a continuous improvement perspective and will form the basis of future exercise demonstrations. None of these observations challenged the Green RAG rating assigned.

The detailed comments of the inspection team and rating for this demonstration will be summarised in a letter to the licensee, inclusive of positive observations and opportunities for learning.

There are no other findings from this inspection that could significantly undermine nuclear safety. The planned interventions set out in the Operating Facilities Division Weapons Sub-division Strategy for Aldermaston site remain valid and will be followed for future inspections.