Office for Nuclear Regulation

Analytical Services (AS) Infrastructure Services - System Based Inspection (SBI)

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, a system based inspection (SBI) of the Analytical Services (AS) ventilation system was planned for October 2018.¬† The purpose of this planned inspection was for ONR to confirm the adequacy of implementation of the licensee’s safety case claims in respect of this system.

As part of each SBI, ONR examines evidence of the adequate implementation of six pre-defined licence conditions.¬† These licence conditions (listed below) have been selected because of their importance to nuclear safety, and are defined within the ONR’s process for delivery of an SBI.

Interventions Carried Out by ONR

LC 10 requires SL to make and implement adequate arrangements for suitable training of those who have responsibility for any operations that may affect safety.

LC 23 requires SL to produce adequate safety cases to demonstrate the safety of its operations, and to identify the operating conditions and limits necessary in the interests of safety.

LC 24 requires SL to make and implement adequate arrangements for the provision of suitable written instructions for undertaking any operation that may affect safety.

LC 27 requires SL to ensure that, before a system is operated, inspected, maintained or tested, there are suitable and sufficient safety mechanisms, devices and circuits properly connected and in good working order.

LC 28 requires SL to make and implement adequate arrangements for the regular and systematic examination, inspection, maintenance and testing of all plant which may affect safety.

LC 34 requires SL to ensure that its radioactive material and radioactive waste is at all times adequately controlled and contained, and that no leak or escape of that material or waste can take place without being detected.

I carried out a two-day, on-site, system based inspection of the ventilation system within AS, utilising specialists from Operational Inspection, Mechanical Engineering and Chemical Engineering. The inspection comprised discussions with SL staff, a plant walk down and reviews of plant records and other documentation.

 Explanation of Judgement if Safety System Not Judged to be Adequate

The ventilation system was judged to be adequate.

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

From the evidence made available to me during this inspection, based on the areas targeted I consider that SL has implemented adequately those claims within the facility safety case that relate to the ventilation system.

In terms of management of the system’s physical condition, I consider that SL’s arrangements are adequate and the projects in place to bring aging areas into compliance with modern standards are proportionate. Evidence provided by SL and along with an on-going ONR regulatory issue gives me confidence that they will be achieved.

Whilst some minor opportunities for improvements were identified, I found LC’s 10, 23, 24, 27, 28 and 34 to be adequately implemented in relation to the systems inspected, I awarded an inspection rating of Green (no formal action) for LC’s 10, 23, 24, 27, 28 and 34.

Conclusion of Intervention

From the evidence sampled during this investigation, I judged that the licensee has implemented adequately the relevant claims within the safety case, and that, there was evidence that the arrangements for all licence conditions I inspected against were also implemented adequately.

I have raised a level 4 Regulatory Issue in relation to minor shortfalls observed during the inspection.