Office for Nuclear Regulation

Compliance inspection of Licence Condition 35 (Decommissioning)

Executive summary

Purpose of Intervention

In accordance with the Office for Nuclear Regulation’s (ONR’s) Sellafield Strategy, each year ONR performs a series of planned compliance inspections of selected licence conditions, targeted at those facilities with significant importance to nuclear safety.

The purpose of this planned inspection was for ONR to determine the adequacy of implementation of the licensee’s formal arrangements for compliance with Licence Condition (LC) 35 (Decommissioning).  Sellafield Limited’s (SL’s) Magnox Reprocessing Facility (MRF) was selected as the target for this inspection because the Magnox Operating Programme (MOP) is due to finish in July 2020, at which time the (MRF) will cease operating and enter into a period of Post-Operation Clean Out (POCO).  POCO is a key enabler for safe plant decommissioning and forms part of SL’s arrangements for compliance with LC 35.

Interventions Carried Out by ONR

On 19 March 2019, I, along with the Magnox Site Inspector, carried out a one-day licence condition compliance inspection of facilities within the Magnox Operating Unit.  The inspection comprised discussions with SL staff, a targeted plant walk down and reviews of plant records and other documentation.

LC 35 requires the licensee to make and implement adequate arrangements for the decommissioning of any plant or process which may affect safety.

As part of my preparation for the delivery of this intervention, the following formal ONR guidance documentation was used:

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 examined evidence of the licensee’s compliance with its arrangements for decommissioning, particularly in respect of preparations for POCO in MRF, and consider, on the basis of my sample, that the licensee is making satisfactory progress.  In addition, I examined evidence of some POCO-related trial work undertaken during the planned outage in 2018; the trials provided results that can feed into POCO delivery and valuable hands-on experience for operators.

Due to resourcing issues, the licensee was unable to provide a plan or programme for the POCO-related activities for the Magnox Decanners prior to the end of reprocessing.  As such, I consider that there is a risk that this delay could impact on the timely removal of material from the Magnox Decanners for co-processing or onward waste management.  I judge this to be a minor shortfall and have raised a regulatory issue to oversee progress.

Conclusion of Intervention

On the basis of the evidence sampled during the inspection, I judge that an inspection rating of Green (No formal action) is appropriate for compliance against Licence Condition 35.  This is because I found that SL has adequately implemented its corporate arrangements for this LC.  One minor shortfall will be progressed via a Regulatory Issue.