Office for Nuclear Regulation

This website uses non-intrusive cookies to improve your user experience. You can visit our cookie privacy page for more information.

Compliance intervention, forming part of the 2014/15 inspection programme for the Capenhurst site

Executive summary

Purpose of intervention

Compliance intervention, as part of the 2014/15 intervention programme for the Urenco UK Limited Capenhurst site.

A reactive meeting was held with the licensee’s Emergency Planning Manager, to discuss aspects of the forthcoming Level One emergency exercise, together with the licensee’s impending provision of a revised licence condition 11 “On Site Emergency Plan”, for ONR Approval.

A reactive meeting was held to discuss a leak from a legacy uranium hexafluoride (“Hex Tails”) cylinder, stored on part of the licensed site leased to Capenhurst Nuclear Services Limited. 

Interventions Carried Out by ONR

As part of the planning for the forthcoming Level One emergency exercise, I held a constructive meeting with the licensee’s Emergency Planning Manager.  We agreed the key elements to be demonstrated by the licensee during the observed exercise. We also discussed the licensee’s impending presentation of the revised “On Site Emergency Plan”, which was imminently to be presented to ONR for Approval.

A meeting was convened by the licensee to discuss an event on the part of the licensed site leased to Capenhurst Nuclear Services Limited. During the licensee’s planned periodic detailed inspection of the stored inventory of ‘type 0236’ legacy uranium hexafluoride (Hex Tails”) cylinders, evidence was found of the leakage of uranium hexafluoride from within one of these ageing full cylinders.  The leakage had self sealed and the amount of activity which had leaked was being assessed by the licensee.  The licensee had promptly applied sealant and bagged the end of the cylinder as precautionary measures.  Personnel access to the scene had been prevented and local airborne activity monitoring had been implemented.  It was agreed that the licensee would promptly issue an ‘INF 1’ event report to ONR, which would include an assessment of the quantity of radioactive materials released from the cylinder.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable.

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

In my judgement, I was content with the detailed scope of the licensee’s proposed Level One Emergency Exercise, to be observed by a team of ONR inspectors.  The licensee had developed a sufficiently challenging exercise scenario and the fine details were readily agreed with the licensee.  I provided regulatory advice regarding some minor improvements to the facilities to be used during the demonstration of the licensee’s emergency arrangements, which were readily accepted by the licensee.

The licensee also discussed the imminent provision of a duly periodically revised ‘on site emergency plan’, for which Approval from ONR was about to be sought.  It was encouraging to note that the licensee had incorporated the latest ONR published guidance for ‘on site emergency plans’ and was providing ONR with a supporting assessment by the licensee of this emergency plan, assessed against the ONR guidance.  This would assist my assessment of the updated emergency plan.

Regarding the licensee’s prompt and detailed initial verbal report of a leak from a type 0236’ legacy uranium hexafluoride (“Hex”) cylinder, stored on the part of the site leased to Capenhurst Nuclear Services Limited, I was content with the initial remedial actions taken by the licensee.  The licensee agreed to provide to provide me with the outcome of the licensee’s licence condition 7 investigation in the short term, alongside the outcome of the licensee’s medium term review of the implications for the continuing long term storage of a significant inventory of ageing ‘type 0236’ legacy uranium hexafluoride (“Hex Tails”) cylinders at Capenhurst.

Conclusions of Intervention

On balance, I concluded that the licensee’s implementation of those aspects of the licence condition 11 emergency arrangements which were inspected during this intervention were adequate.

Regarding the legacy uranium hexafluoride (“Hex Tails”) cylinder leakage event, I concluded that the licensee’s had promptly informed me and that the responses made by the licensee were timely, proportionate and appropriate.  I concluded that the licensee had adequately implemented those aspects of the licence condition 7 arrangements inspected during this intervention.