Skip to content

Sellafield LC22 - Readiness inspection

  • Site: Sellafield
  • IR number: 21-160
  • Date: January 2022
  • LC numbers: 22

Executive summary

Purpose of Intervention

On the 26 January 2022, the Office for Nuclear Regulation (ONR) undertook an intervention on the Sellafield Limited site to:

  • Inspect Sellafield Limited readiness to implement a new safety case covering Plutonium Contaminated Material (PCM) operations in the Mixed Oxide Fuel (MOX) Demonstration Facility (MDF).
  • Gain evidence to support ONR’s permissioning of this activity.

The purpose of the intervention was to inspect Sellafield Limited implementation of their Licence Condition (LC) arrangements under LC22 “Modification or experiment on existing plant”. The intervention sought to gain evidence that Sellafield Limited is in a suitable position to implement the PCM safety case and to safely commence PCM operations and export from the MDF.

This intervention was undertaken in accordance with ONR’s Sellafield strategy to permission those activities which have been identified as presenting a higher risk.

This intervention record (IR) provides a record of the readiness inspection findings to support ONR’s permissioning decision relating to the regulatory Hold Point 505 (HP 505), which requires the implementation of a new safety case for PCM operations at the MDF. This decision will be recorded in ONR’s Decision Record ONR-SDFW-DR-19-005.

Interventions Carried Out by ONR

The primary focus of this intervention was to inspect the MDF plant, processes and people, and to assess Sellafield Limited readiness to safely commence PCM operations. The ONR inspection comprised of desktop-based discussions and on-plant inspection.  We focused the inspection on the following key factors, which we consider important regarding Sellafield Limited readiness to implement the PCM safety case and to safely commence PCM operations within MDF:

  • Training;
  • Duly Authorised and other suitably qualified and experienced persons;
  • Operating rules;
  • Operating instructions;
  • Control and supervision of operations;
  • Safety mechanisms, devices and circuits; and
  • Examination, inspection, maintenance and testing.

During the inspection we examined evidence linked to these factors, including supporting arrangements that implement associated safety case limits and conditions. 

We inspected against LC22 (1), which requires the Licensee to “make and implement adequate arrangements to control any modification or experiment carried out on any part of the existing plant or processes which may affect safety”.

The following ONR guidance was used as a basis of regulatory expectations for the inspections:

  • ONR-INSP-GD-059 Revision 8, Guidance for Intervention Planning and Reporting.
  • ONR-INSP-GD-064 Revision 5, General Inspection Guide.
  • NS-INSP-GD-022 Revision 7: LC 22: Modification or Experiment on Existing Plant.

Explanation of Judgement if Safety System Not Judged to be Adequate

This was not a system-based inspection.

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

Based on the evidence sampled during this intervention several outstanding issues were identified in the following areas:

  • Safety Case Documentation: Several documents are in draft status or currently being developed. In addition, several documents need to be aligned with the latest version of the Safety Case Implementation Plan.
  • Training of Duly Authorised Person and other operators is ongoing therefore incomplete.
  • Facility readiness: Glovebox identification and marking of laydown areas is incomplete.
  • Sellafield Limited readiness governance process has yet to be completed.
  • Several actions remain outstanding from the internal regulator’s (Nuclear Intelligence and Internal Oversight (NI&IO)) review.

Conclusion of Intervention

Taking the above key findings into account, sampled at the time of the inspection, we judge that the Licensee continues with the process of development and implementation of the PCM safety case and this process is currently incomplete. We therefore consider that this readiness inspection did not provide the requisite evidence to support the decision to permission release of HP 505.  As a result, this readiness inspection was not rated. This readiness inspection highlighted areas of focus for the Licensee to consider prior to PCM safety case implementation.  A further intervention will be required to follow-up the findings of this intervention prior to permissioning  release of HP 505.