Office for Nuclear Regulation

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Sellafield - Planned Licence Condition 22 Readiness Inspection at the Pile Fuel Cladding Silo (PFCS) on the Sellafield site in support of retrievals access penetrations (RAP) operations

Executive summary

Purpose of intervention

The Office for Nuclear Regulation (ONR) undertook an intervention at the Pile Fuel Cladding Silo (PFCS) facility on the Sellafield site to inspect Sellafield Ltd's (SL) readiness to commence retrievals access penetrations (RAP) operations. This will involve six holes being cut into the silo wall behind the six already-installed containment doors. This work is a critical enabler to the longer-term programme to access and retrieve the waste from the facility.

The purpose of the intervention was to inspect SL's implementation of the RAP operations safety case which has been made under its licence condition (LC) 22 arrangements. This is to gain confidence that the safety case is understood by the licensee and that the plant, people and processes will be in place prior to commencing hole coring and cutting. These activities are the subject of a hold point (HP6 / line 42 - TRIM 4.4.2.14609.) of the Sellafield hold point control plan. The findings of the inspection will inform ONR's decision to give its agreement to the commencement of RAP operations.

The inspection is in line with ONR's strategy to ensure the timely and effective delivery of activities to support hazard and risk reduction at PFCS and is in accordance with the permissioning strategy for RAP operations as described in the ONR decision record ONR-SEL-DR-16-009 (TRIM 2016/211653).

Interventions Carried Out by ONR

The focus of the intervention was to inspect the relevant plant areas, processes and people to assess their readiness for the commencement of RAP coring and cutting activities. The inspection comprised discussions with RAP rig operators, PFCS plant supervisors and RAP operations project managers and technical support personnel, as well as a facility inspection of PFCS and the RAP operations rig which was undertaken against LC 22 in accordance with ONR Technical Inspection Guide (TIG) NS-INSP-GD-022 Revision 3.

Explanation of Judgement if Safety System Not Judged to be Adequate

This was a readiness inspection and a judgement has been made on the adequacy of the implementation of the RAP operations safety case by SL on the date of the inspection.

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

In terms of the process and people associated with RAP operations, the inspection team found good evidence of preparedness for the start of RAP coring and cutting activities. We found evidence of close involvement of senior PFCS management, strong co-operation between the licensee and the main contractor (BCNS) and sub-contractor (Holemasters Ltd), appropriate written command and control arrangements with which staff at all levels demonstrated appropriate knowledge and understanding.

In terms of the plant and equipment associated with RAP operations, we (as expected given some of delays in the licensee's programme) confirmed that a significant amount of work remains to be completed. Whilst the RAP rig had been fully installed and positioned, electrical energisation, commissioning, some further equipment installation, radiological barrier installation and signage remain to be completed. At the time of the inspection, the RAP rig and the key other facility areas (PFCS control room, emergency vehicle access routes, personnel entry to the PFCS facility and to the PFCS construction area) were seen to be in good condition, well-kept and ready to support RAP operations.

The RAP Operations Project Manager stated that the core team of personnel required for RAP operations had completed all site-specific (SOCWAS) and task-specific training requirements; however, from the evidence provided, in the form of a training matrix, the inspection team were unable to gain confidence because the matrix appeared to be incomplete in a number of areas and did not include the Holemasters Ltd personnel. We requested that an updated training matrix be provided to ONR and we noted that the SL Internal Regulator would be in a position to provide final confirmation in this area as part of its planned Independent readiness review due to commence on 27 February 2017.

The inspection provided sufficient information to enable the ONR Human Factors Specialist Inspector to close-out the outstanding areas of his assessment of the RAP operations safety case associated with the recommendations in ONR-SDFW-AR-16-069 (TRIM 2017/9943).

Conclusion of Intervention

I consider that the licensee is approaching a state of readiness for the commencement of RAP operations; although it is noted that because of some recent licensee programme delays, some significant plant and equipment work remains outstanding. Based on discussions with the licensee's staff and on the status of the plant at the time of the inspection, I do not have any concerns that this remaining work will be completed prior to the commencement of RAP operations.

Other than the need to complete the remaining physical works, the inspection identified no significant concerns that would prejudice ONR granting agreement to the start of hole cutting activities. However, further assurance in a number of areas is needed and I will work with the SL Internal Regulator to seek this prior to recommending issue of the LI.

It is my opinion that an inspection rating of GREEN (no formal action required) is appropriate.