Office for Nuclear Regulation

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Inspection of human factors aspects of Residues Transfer Project

Executive summary

Purpose of intervention

Given the reliance upon operators to prevent faults, human factors aspects are a key element of ONR's permissioning of the Residues Retrieval Project. This inspection at the Sellafield site was part of a planned engagement with Sellafield Limited in support of ONR Sellafield Programme's Objective 7 (to undertake interventions to ensure delivery of activities that will reduce the risk profile in the decommissioned facilities at the Sellafield site).

Interventions Carried Out by ONR

The inspection was focused upon gaining confidence that Sellafield Limited's approach to human factors aspects of the trials is in line with Relevant Good Practice. The inspection looked at compliance with Licence Conditions 10 (Training) and 22 (Modifications to Existing Plant) and included:

Explanation of Judgement if Safety System Not Judged to be Adequate

N/A - this was not a Safety System inspection.

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

My inspection rated Licence Condition compliance as follows:

The safety case for the chosen option for recovery of degraded residue bottles has been completed. The retrievals equipment is not expected to be available until mid to late September as this is a bespoke item. It is acknowledged that further training will be required to ensure operators are suitably qualified and experienced for this operation. This option will go for Sellafield Limited internal approval on the 4 August. I noted that the timeline for commencement of retrievals was prior to the recovery equipment being available. Sellafield Limited provided assurance that, based on trials data, a safe state could be maintained without the equipment being available and there would be no delay to the project. It was noted that if a higher rate of degraded bottles is found, this could delay the programme. Assurance was given that this rationale is substantiated in the safety case. I requested that Sellafield Limited provide the relevant documents to ONR for information/assessment as necessary.

With regard to training, I found training had commenced (and is ongoing) and was following the Systematic Approach to Training, in line with Sellafield Limited arrangements and ONR expectations. Inspection of the presentation material, the lesson plan and assessment indicated that the module provided good coverage of the safety case and of the important aspects of the task and the project's strategic importance to Sellafield Limited. The on-the-job training was focused upon demonstrating task competence and offered good opportunities to develop techniques of achieving tasks 'right first time'. Operators displayed a good level of hazard awareness, and appeared comfortable performing the task, given the context of the training programme. I offered some advice to the project to enhance the training; this related to increasing the focus on safety significant/complex task steps and testing operators understanding of why the task is undertaken in a particular way as well of knowledge of what is done.

Procedural support was found to be at a mature level of development. One issue remains unresolved and that is how the project will assure procedural compliance given the Continuous Use status of the procedures (this requires the procedures to be in hand and followed step-by-step throughout, which is not practicable when undertaking tasks in glove ports) and the significant number of administrative controls needed to implement limits and conditions. I provided advice to the project for their consideration and further advised consultation with Sellafield Limited's own human factors specialists to assure an ALARP solution.

Sellafield Limited provided good evidence that the team were actively looking for opportunities for task optimisation both in design and task support. This has identified a number of simple task improvements which, when aggregated are likely to provide assurance that the task risks are ALARP. I was encouraged by the level of operator engagement; they reported being involved from project inception and appeared comfortable in challenging and suggesting improvements.

Conclusion of Intervention

Operators expressed pride in being involved in this project due to its strategic importance; they also stated that despite the project's organisational profile and the importance of meeting deadlines, high levels of nuclear safety have been maintained. They all reported feeling empowered to challenge and to offer observations for task improvements. I consider this to be an important positive finding and one that should be examined in more detail in ONR's readiness inspection.

Based on the inspection evidence I am content that the trials are providing a suitable validation of the task design from a human factors perspective. The inspection did however identify minor areas for improvement for Sellafield Limited's consideration. Implementation of these will provide further confidence in advance of the planned readiness inspection. There is currently one significant gap and that is in the training and validation of reasonably foreseeable recovery tasks. Sellafield Limited provided assurance that this will be developed and implemented in appropriate timescales.