To conduct a system inspection, attend a Level 4 meeting and undertake routine regulatory interactions with Sellafield Limited
- Site: Sellafield - Magnox
- IR number: 14-103
- Date: July 2014
- LC numbers: 10, 23, 24, 27, 28, 34
Purpose of intervention
This intervention was undertaken on 21 - 24 July 2014 at Sellafield Limited's Sellafield nuclear licensed site in Cumbria.
One of the strategic objectives of Office for Nuclear Regulation (ONR) is to undertake a coordinated programme of safety related compliance inspections on nuclear licensed sites in relation to arrangements for compliance with the Health and Safety at Work etc Act 1974 (HSWA'74) and the Energy Act 2013 (TEA'13). The Nuclear Installations Act 1965 (NIA'65) is a key Relevant Statutory Provision of TEA'13 that provides for a nuclear site licence to be granted to a named corporate body to install or operate specified nuclear installations in a defined location. NIA'65 requires ONR to attach to each nuclear site licence such conditions as it considers necessary or desirable in the interests of safety or with respect to the handling, treatment and disposal of nuclear matter.
Inspection of Licence Condition (LC) compliance at nuclear licensed sites is an important part of ONR's activities. ONR's Sellafield Programme has defined a programme of system inspections and LC compliance inspections that focuses on those parts of the site and activities where the risk or hazards are most significant. The system inspection carried out within this intervention forms part of that programme.
Interventions Carried Out by ONR
The intervention comprised:
- undertaking a system inspection of system 1.08c 'Solvents and Reagents' of the plutonium purification cycle of the Magnox Reprocessing Plant;
- attending an update session on the Glovebox Improvement Programme which is underway in the Magnox Reprocessing Plant;
- attending a routine Level 4 meeting with the Magnox Operating Unit lead team;
- and undertaking routine information exchange with Sellafield Limited (the Licensee).
The system inspection sought to determine whether the Magnox Reprocessing Plant plutonium purification cycle solvent and reagent system meets the requirements of the safety case and is adequate. The implementation of the Licensee's arrangements for the following LCs were tested during the system inspection:
- 10 'Training'
- 23 'Operating Instructions'
- 24 'Operating Instructions'
- 27 'Safety Mechanisms'
- 28 'Examination, Inspection, Maintenance and Testing'
- 34 'Leakage and Escape of Radioactive Material and Radioactive Waste'
ONR routinely engages with Licensees formally and informally in order to undertake its regulatory duties efficiently and effectively. During this intervention I engaged with the Licensee formally (at a Level 4 meeting) and informally (at an update meeting and an information exchange session).
Explanation of Judgement if Safety System Not Judged to be Adequate
The solvent and reagent system of the Magnox Reprocessing Plant plutonium purification cycle was judged to be adequate.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
For the solvent and reagent system of the plutonium purification (PP) cycle of the Magnox Reprocessing Plant I judged the following IIS ratings to be appropriate:
- LC10 - IIS rating 3 (adequate): The Licensee is putting in place new arrangements for training. My inspection indicated that the material produced to date was adequate to provide increased competency assurance for solvent and reagent tasks. Whilst potential improvements were identified, these were offered for consideration and though they would likely lead to a better IIS rating, they do not compromise the level of competence that the Licensee could demonstrate. Training records for solvents and reagents were up to date and indicated all relevant staff were either trained or suitable plans were in place. Based on this, I judged an IIS rating of 3 (adequate) to be justified.
- LC23 - IIS rating 3 (adequate): I confirmed that the safety case specifies limits and conditions with respect to solvents and reagents, and that these limits and conditions are specified in operating and alarm response instructions. Where there was a tolerance to the limits I confirmed upper and lower limits were specified in either the safety case or instructions. I confirmed that a number of operating assumptions in the safety case were captured in operating instructions. Based on my sampling inspection, I judged an IIS rating of 3 (adequate) to be justified.
- LC24 - IIS rating 3 (adequate): I sampled a range of operating instructions, maintenance instructions and alarm response instructions. I judged that the written instructions sampled were clear and unambiguous, and did relate to ensuring compliance with the limits and conditions derived from the safety case. I judged an IIS rating of 3 (adequate) to be justified. When the Licensee has completed the ongoing programme of work to transition to Continuous Use Instructions a better IIS rating is likely to be justifiable.
- LC27 - IIS rating 3 (adequate): I sampled a number of key Safety Mechanisms (SMs) from all the solvents and reagent feeds to the PP cycle. Based on my sample, there are suitable and sufficient SMs for this system, they are being inspected and are in good working order. Where individual SMs were not available I confirmed appropriate substitution arrangements were in place. Based on my sampling inspection, I judged an IIS rating of 3 (adequate) to be justified.
- LC28 - IIS rating 3 (adequate): I sampled the maintenance schedule, maintenance instructions and maintenance records for key components of the system and found no deficiencies. Based on this I judged an IIS rating of 3 (adequate) to be justified.
- LC34 - IIS rating 3 (adequate): I sampled the arrangements in place to ensure integrity of the barriers to leakage and escape in the PP cell and for the means of detection of leakage. I judged that the design of the PP cycle, combined with the ongoing inspection regime, facilitates containment of radioactive materials, and adequate arrangements are in place to detect any leakage that does occur. Based on this I judged an IIS rating of 3 (adequate) to be justified.
Overall, I judged that the Licensee has appropriate plant and arrangements in place and available to ensure that the solvents and reagents entering the PP cycle of the Magnox Reprocessing Plant are consistent with the defined specifications. Based on this system inspection, I conclude the system meets the requirements of the safety case and is adequate.
The Licensee provided evidence of progress against the Glovebox Improvement Programme that is ongoing within the Magnox Reprocessing Plant. Based on the evidence provided, I am satisfied that the condition of the gloveboxes that have been subject to the improvement programme represent a significant improvement relative to their original condition, moving closer to Relevant Good Practice. I requested the Licensee's own site inspection function to undertake an inspection (including a plant walk down) of the completed gloveboxes and to provide a report to me summarising the findings. The Licensee's own site inspection function will continue to monitor progress against the improvement programme to completion, providing progress statements to me if requested.
ONR routinely exchanges information with Licensees. In this instance the exchange included discussions on an event report and an interaction with a safety representative.
Conclusion of Intervention
One action was placed as a result of this intervention, which was completed by the Licensee prior to this report being issued. I brought a number of conventional safety issues to the Licensee's attention which I will follow up as part of my normal regulatory interaction with the Licensee. Based on the evidence gathered, no significant matters have been identified that are likely to impact on nuclear safety on the Sellafield site at this time.