- Site: Sellafield
- IR number: 21-012
- Date: May 2021
- LC numbers: 32, 35
Executive summary
Purpose of Intervention
The purpose of these inspections was for ONR to determine the adequacy of implementation of Sellafield Limited (SL) arrangements for compliance with LC 35 (Decommissioning) at the Thermal Oxide Reprocessing Plant (THORP), and LC 32 (Accumulation of radioactive waste) at the Spent Fuel Services Fuel Storage Facilities. The overall adequacy of SL's site-wide LC 35 and LC 32 arrangements is considered separately in other ONR interventions. In addition to these compliance inspections, the Site Inspector for THORP and Fuel Storage undertook an observation of SL’s Friday Exercise (FRIDEX), the purpose of the observation was to seek assurance of SL’s emergency arrangements.
The Office for Nuclear Regulation (ONR) undertakes all regulatory interaction with the licensee SL against a strategy defined by the ONR Sellafield, Decommissioning, Fuel and Waste Division. The planned inspection schedule for 2021/ 22 identifies the Licence Conditions (LCs) that will be inspected during this period.
Interventions Carried Out by ONR
I carried out two planned compliance inspections jointly with the Environment Agency:
- LC 35 at THORP, focused on the requirements for transition into, and delivery of the Post Operational Clean Out (POCO) phase of decommissioning.
- LC 32 at Fuel Storage (formally the Oxide Fuel Storage Group, and now part of the Spent Fuel Services Operating Unit) focused on storage of radioactive waste and management of temporary laydown areas.
The Site Inspector for THORP and Fuel Storage also undertook an observation of the Sellafield Friday exercise from the Summergrove Facility.
The interventions comprised discussions with SL personnel, reviews of SL documents, and for the LC 32 inspection, a plant walkdown.
The intervention was performed in line with ONR's guidance requirements (as described in our technical inspection guides) in the areas inspected.
Explanation of Judgement if Safety System Not Judged to be Adequate
Not applicable since this was not a safety system-based inspection.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
POCO has begun in THORP with the low-pressure washout of the Shear Cave, while other areas remain in operation. A consolidated and accurate POCO delivery schedule is being worked to, which includes waste management and characterisation activities. Appropriate governance is in place for managing POCO decisions on a daily basis through the POCO Support Group. I found that two of the documents required to be reviewed and approved before transition into POCO are only available in draft form. I have raised an ONR Level 4 Regulatory Issue (lowest level) to monitor progress with finalising them.
Fuel Storage has have made improvements in radioactive waste management since the last inspection in 2019, reducing the amount of historic waste, securing resources, and reducing the number of waste laydown areas. I observed three minor shortfalls against the SL requirements relating to the storage of radwaste (signage, plant walkdowns, and recording of temporary laydown areas in the inventory). I have raised a Level 4 Regulatory Issue for the facility to carry out a gap analysis between its waste storage practices and the SL corporate arrangements and for SL to create an improvement plan for any non-conformances.
The FRIDEX arrangements for the current 8-week period are focussed on a “Back to Basics” campaign, allowing each of the duty roster teams to concentrate on working in small teams and receive coaching. Consequently, this was not an exercise of the full Emergency Duty Team capability. The Inspector who observed FRIDEX has made a number of minor observations in relation to arrangements when working remotely and these will be passed to the Inspector responsible for consideration.
Conclusion of Intervention
In relation to LC 35, I judged that a rating of ‘Green’ is warranted based on the overall implementation of requirements for delivery of POCO, with a minor non-conformance identified relating to the review and sign-off of documentation.
In relation to LC 32, I judged that a rating of ‘Green’ is warranted based on clear reduction in the accumulation of radwaste since the last inspection, with some minor non-conformances against the SL arrangements for waste storage.
The observation of FRIDEX was unrated, however that were no significant concerns identified that require immediate regulatory action, a number of minor observations have been passed to the Inspector responsible for consideration.