Office for Nuclear Regulation

Sellafield – Inspection ID: 50842

Date(s) of inspection:

  • January 2023

Aim of inspection

In accordance with the Office for Nuclear Regulation’s (ONR’s) Sellafield Strategy, each year ONR performs a series of planned inspections to seek assurance of compliance against selected licence conditions, targeted at those facilities with significant importance to nuclear safety. One such inspection was performed focusing on the Beta Gamma Operating Unit within the Remediation Value Stream to assess compliance with Sellafield Limited’s corporate arrangements for Licence Condition (LC) 22 (Modification or experiment on existing plant), in order to inform a regulatory judgement regarding the licensee’s compliance with its legal duties under the nuclear site licence.

Subject(s) of inspection

  • LC22 – Modification or experiment on existing plant – Rating – Green

Key findings, inspector’s opinions and reasons for judgement made

The inspection was undertaken on 17 January 2022 by the ONR Site Inspector for the Remediation Value Stream.

The inspection comprised discussions with Sellafield Limited personnel, review of records, documents and processes specific to the Beta Gamma Operating Unit of the Remediation Value Stream. I sampled several records including   dashboard reports, trend and health reports, the  Annual Review of  LC22 Process Performance and several open and closed PMP forms and supporting documents.

From a mixture of sampling records and interviewing Sellafield Limited personnel, I saw evidence that  Sellafield Limited has suitable and sufficient processes in place to monitor the Plant Modification Proposals (PMPs). The control of live and overdue PMPs was adequate. The categorisation, implementation and closure of PMPs is in line with Sellafield Limited’s corporate arrangements.

Sellafield Limited proactively identified that the processes for review, oversight, audit and extension of Temporary Plant Interventions (TPI) and Redline Drawings  were not aligned with the corporate arrangements and  I was assured that improvement measures have already put in place to address these.  Sellafield Limited also provided me with assurance that   the  Configuration Management Improvement Plan will be included in the next  Annual Review of  LC22 Process Performance. The training records for several personnel were completed and in-date.


I consider that, on the basis of evidence sampled at the time of this inspection, the licensee has broadly implemented  its corporate arrangements for compliance with LC22 (Modification or experiment on existing plant) at the Beta Gamma Operating Unit. I, therefore, consider that an inspection rating of Green (No Formal Action) is appropriate.