- Site: Dounreay
- IR number: 21-120
- Date: November 2021
- LC numbers: 22, 28
Executive summary
Purpose of Intervention
This inspection included a systems-based inspection and checking compliance with Licence Conditions (LC) in accordance with the 2021/22 Integrated Intervention Strategy (IIS) for Dounreay to confirm that the licensee is controlling its hazards and complying with its statutory obligations.
Interventions Carried Out by ONR
ONR undertook inspections of the site’s arrangements and their implementation against the requirements of the following LCs:
- LC22 - Modification or experiment on existing plant.
- LC28 - Examination, inspection, maintenance, and testing.
The Systems-Based Inspection (SBI) focused on waste operations within the Low Level Liquid Effluent Treatment Plant (LLLETP) and Low Active Drain (LAD). The SBI examined the adequacy of the safety case and its implementation against the requirements of the following licence conditions (LC):
- LC10 – Training.
- LC23 - Operating rules.
- LC24 - Operating instructions.
- LC27 - Safety mechanisms, devices, and circuits.
- LC28 - Examination, inspection, maintenance, and testing.
- LC34 - Leakage and escape of radioactive material.
The intervention also provided the opportunity to conduct a readiness review within D1208 as part of ONR’s considerations for releasing the regulatory hold point on the commencement of active commissioning for the transfer of HEU Liquors as part of the ongoing material consolidation programme. It also provided the opportunity to review progress against matters raised in response to observations from the recent Site Level 1 Safety Demonstration Exercise.
Explanation of Judgement if Safety System Not Judged to be Adequate
We consider that safety systems we examined to support operations within the LLLETP and LAD to be adequate against the requirements of the above licence conditions.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
The LC22 compliance inspection focused on the adequacy of the corporate arrangements and their implementation in support of work being conducted within the reactors decommissioning operational area and the waste operations directorate. We are satisfied that DSRL’s arrangements meet the regulatory requirements of LC22. We are also satisfied that their implementation in support of the work packages inspected, demonstrate adequate identification and control of the hazards associated with those activities.
The LC28 compliance inspection focused on the adequacy of the corporate arrangements and their implementation in support of maintenance activities being conducted within the reactors decommissioning operational area and the waste operations directorate. We are satisfied that DSRL’s arrangements and, their implementation in support of the examination, inspection, maintenance and testing of those safety systems inspected meet the regulatory requirements of LC28. Minor shortfalls against relevant good practice are already being addressed by DSRL as part of a broader internal governance improvement programme.
The SBI conducted at the LLLETP and LAD examined the staff’s understanding of the key outcomes from the safety assessment of the activities conducted within the plant. We then examined how the limits and conditions identified within the safety assessment had been captured and reflected in the associated operating instructions and the maintenance of safety related plant and equipment. This inspection included a plant visit to the LLLETP, where we took the opportunity to assess the understanding operators had regarding the hazards and associated limits and conditions associated with the activities being undertaken at that time. We also examined the training undertaken by operations staff and we examined how the arrangements addressed potential leakage and escape of radioactive material and radioactive waste.
Overall we were satisfied that the limits and conditions and safety related plant and equipment identified within the safety assessment had been adequately captured within the associated operational and maintenance documentation reviewed, that the training records examined reflect the level of understanding expected of staff and, that the arrangements provide an adequate demonstration against the requirements regarding the control of leakage and escape of radioactive material and radioactive waste.
Conclusion of Intervention
Overall, we consider that the safety justification supporting the activities undertaken within the LLLETP and LAD has been implemented adequately against the requirements of those licence conditions covered by the SBI. We also consider that DSRL’s arrangements for LC22 and LC28 in the areas inspected demonstrated adequate compliance against the regulatory requirement. We did not identify any matter impacting on nuclear safety that required any further immediate regulatory action.