Office for Nuclear Regulation

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Planned intervention at Research Restoration Sites Ltd's Winfrith licensed site, undertaken as part of a series of planned interventions outlined in the ONR Plan for the Regulation of the Harwell and Winfrith Sites 2014/2015

Executive summary

Purpose of intervention

This report outlines the findings from an inspection of Research Sites Restoration Ltd's (RSRL's) Winfrith licensed site, undertaken as part of interventions outlined in the ONR plan for the regulation of the Harwell and Winfrith sites 2014/2015. The interventions undertaken consisted of both planned and reactive activities

Interventions Carried Out by ONR

There is a requirement that over a five year period ONR will inspect aspects of the important systems for safety identified in the safety case for the installations it regulates. The aim of these inspections is to ensure adequate implementation of the safety functions outlined in the safety case through operational arrangements, limits and conditions and other claims as described in arrangements made under several licence conditions.

The decommissioning programme for SGHWR has now entered the primary containment deplanting stage. The primary containment has been modified to enable safe access and egress into the containment through an airlock system to undertake activities required to support asbestos removal. In addition, RSRL is constructing a modular containment structure to provide workshops for managing disposal of asbestos waste and processing radioactive Low Level Waste (LLW).

The principal activity of the inspections detailed in this report has focussed on the modular containment structures used for decommissioning and decontamination activities in SGHWR. Additionally the Annual Review of Safety for Harwell and Winfrith was held and a number of separate inspections looking at conventional safety and radiation protection were undertaken in a number of facilities by ONR specialist inspectors.

Explanation of Judgement if Safety System Not Judged to be Adequate

From the inspection, I judge that overall the modular containment structures meet the requirements of the safety case and are adequate.

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

Inspection of the SGHWR modular containment structures confirmed that implementation of the safety system was either adequate or of a good standard for the licence conditions considered.

During March 2014 RSRL undertook a joint Level 1 Emergency/Counter Terrorist (CT) Exercise. The demonstration of emergency arrangements was considered to be adequate. No significant observations arose, although there were three matters that need to be addressed promptly to support ONR's expectation to witness site emergency and CT exercises every two years rather than annually.. In response to these observations, ONR witnessed a focussed exercise to demonstrate that improvements to address these matters had been successful. In general the exercise demonstrated prompt call-out and establishment of the site emergency control centre (SECC); the decision time to lock down of the site was reduced; and revised arrangements for communicating completion of staff accountancy and security sweeps by site facilities were adequately demonstrated.

A number of plant walk-downs/inspections were undertaken by different specialist inspectors. None of these highlighted any specific concerns with the exception of some conventional safety issues identified in SGHWR and Dragon, which RSRL agreed to address promptly. In general all inspections within SGHWR commented on the high standards being adopted by the decommissioning project team at all levels.

The ONR site inspector and ONR's Superintending Inspector for the Magnox and Restoration sites attended the Annual Review of Safety (ARoS). RSRL provided overviews of their safety performance at Winfrith and Harwell identifying what had gone well, areas that had not been positive and plans for the following year with ongoing safety improvements. ONR confirmed that performance during the past year continued to improve and that inspections are providing evidence of a much improved safety culture within the organisation.

Conclusion of Intervention

From the evidence gathered during this intervention, I do not believe there are any matters that may immediately affect nuclear safety.