Office for Nuclear Regulation

Readiness inspection for restart of Magnox reprocessing following a periodic outage 

Executive summary

Purpose of Intervention

The Office for Nuclear Regulation (ONR) undertakes all regulatory interaction with the Sellafield site licensee (Sellafield Limited, SL) against a strategy defined by the ONR Sellafield Sub Division. In accordance with that strategy, ONR planned to undertake a readiness inspection as part of preparations to release a hold point placed on SL prior to feeding fuel to the dissolver. 

Licence Condition (LC) 28 relates to examination, inspection, maintenance and testing (EIMT) is one of the prime drivers of the shutdown in conjunction with the requirement to undertake statutory inspections of pressure systems and undertake a physical inventory take (PIT) and physical inventory verification (PIV) for safeguarding purposes. The annual shutdown allows access to plant that is not available during operations.  On a three-yearly basis, the facility shuts down to undertake more intrusive EIMT, which may involve additional washouts of parts of the plant to allow personnel access.

The purpose of this inspection was for ONR to determine whether SL had undertaken the proposed shutdown activities, understand whether there were any EIMT activities that could not be completed and any related justifications.  This will then be used as evidence to support removal of the regulatory hold point and allow feeding fuel to the dissolver.

Intervention Carried Out by ONR

I carried out a 1.5 day inspection, supported by a structural integrity specialist inspector. Ahead of the inspection, SL provided ONR a copy of relevant arrangements, plans, listing of 3-yearly planned maintenance scheduled and technical information, as requested.

LC28 requires the licensee to make and implement adequate arrangements for the regular and systematic EIMT of all plant which may affect safety.

My inspection, comprised discussions with SL staff, examination of selected samples of plant documentation, and physical inspection of selected samples of EIMT activities.

Explanation of Judgement if Safety System Not Judged to be Adequate

This was not a system based inspection, and therefore no judgement has been made of the adequacy of implementation of any part of the safety case.

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

I found that SL has implemented a systematic process with good governance to ensure that all outage scope is controlled and completed, as necessary.  The EIMT undertaken during the outage was all completed or on track to be completed. I consider that for the areas sampled SL has demonstrated compliance with the requirements of LC28 and I saw no significant shortfalls that would prevent the hold point from being released.

SL has undertaken due process in considering options relating to continued operation, following a pin-hole leak being discovered in the steam strip pre-heater. SL has considered the safety impact of continued operation and shown it to be negligible. I will consider the associated plant modification proposal made as part of the decision to allow restart.

From the areas sampled, I identified one level 4 Regulatory Finding (ONR Regulatory Issue) during this inspection, related to the use and recording of pre and post job briefs. I will gather further intelligence from SL’s internal regulator feedback prior to deciding any further action.

Conclusion of Intervention

I consider that, on the basis of evidence sampled at the time of this inspection, the licensee has implemented adequately their arrangements for compliance with Licence Condition 28 and I did not identify anything that will prevent the plant returning to operation following the outage as planned (pending completion of outage activities and removal of the regulatory hold point). I therefore consider that an inspection rating of Green (No Formal Action) is merited.