Office for Nuclear Regulation

Sellafield - Package Design Group management arrangements

Executive summary

Purpose of Intervention

This intervention is one of a series of interventions planned as part of the ‘SDFW (Sellafield) Intervention Strategy covering onsite transport operations of radioactive material supporting hazard and risk reduction on Sellafield Site’.

Information from this inspection will also support the application from Magnox Limit to transfer the M2 Irradiated Fuel Flask Design Authority from Magnox to Sellafield Ltd.

Purpose of Intervention

The intervention took place at Hinton House, Risley. The purpose of this planned inspection was to:

Interventions Carried Out by ONR

On 25th June 2019, we carried out a management system inspection of the SL Package Design Group to review their management arrangements covering the design, approval, use and ongoing operations of onsite packages used at Sellafield. This intervention focused on the SEP package as the example to allow the evidence obtained to feed into the ongoing assessment work to support release of regulatory hold points for commencement of waste retrievals from MSSS. This was a desk top inspection.

The intervention focused on the following transport thematic areas:-

Though this was an ‘onsite’ only intervention, we used ONR guidance ‘Compliance Inspection of Transport Arrangements in the Nuclear Sector NS-INSP-GD-069’ as the bases for the inspection.

This inspection did not look at the SEP package design in detail as this is being assessed via other interventions and ongoing assessments to support permissioning activities across the MSSS stream.

Explanation of Judgement if Safety System Not Judged to be Adequate

N/A – not a System/Structure Based Inspection.

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

The corporate Package Design management arrangements appear to be adequate but are currently under review to ensure that they are fit for purpose to allow SL to become the Design Authority for the M2 Flask design.

It appears that the Package Design Group has been implemental in ensure that the SEP package design and operation requirements have been coordinated across the various facilities in the MSSS stream that will interface with it. This has been a challenge with competing requirements by the operational facilities and that the design has evolved over a period of 20 years. It was noted that the design justifications, change control and operational documentation to support the SEP package design has been dispersed across multiple documents and held under various projects. It is recommended that the Design team pulls this information together into one location and review to ensure it has the evidence needed to support the transport safety case requirements.

SL had to freeze the SEP package design to put the package into manufacture to support commencement of waste retrievals from MSSS.  In some instances SL’s understanding of the nature of MSSS waste has evolved since the package design was frozen (for example the rate of acute hydrogen release) so SL is currently assessing the impact of the overpressure on the package design.

Training and Responsibilities. Additional information was requested that has now been supplied. The description given at the time of the inspection appears to coincide with the information supplied afterwards but this has not been validated. As part of the ongoing permissioning work. I have requested to sit with SL and go through the SEP package transport safety case and it would be an opportune time to confirm the statement made above.

Conclusion of Intervention

Based upon the evidence sampled during the inspection, we judged that an inspection rating of Green (No formal action) is appropriate for compliance against the above listed transport thematic areas.