Office for Nuclear Regulation

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Dungeness B - Interventions for the Through-Life Management of Pressure Systems

Executive summary

Purpose of intervention

The purpose of this intervention was to conduct an inspection of the arrangements in place at Dungeness B power station (DNB) for management of compliance with the Pressure Systems Safety Regulations (PSSR). The work was carried out as part of the planned intervention task sheet TS024 – “Through-Life Management of Flow Assisted Corrosion (FAC) and Pressure Systems Safety Regulation (PSSR) Compliance on AGR Sites”.

I carried out this inspection accompanied by an ONR Structural Integrity Inspector. The inspection was took place on 15 and 16 November 2016 and involved discussions with staff from EDF Nuclear Generation’s (NGL) and Bureau Veritas (BV). BV are employed by NGL in the role of competent person, as defined within PSSR.

Interventions Carried Out by ONR

The objective of the inspection was to obtain information relating to NGL’s arrangements for managing compliance with PSSR, in order to identify any areas of relevant good practice, or shortfalls to our expectations. Particular emphasis was placed on the following:

To assist with PSSR compliance, NGL have produced an internal code of practice “Safety Management of Pressure Systems”, BEG/SPEC/SHE/COP/036 (COP/036). The document identifies Regulations within PSSR and assigns responsibilities for complying with them. I have also used this document to assess the adequacy of arrangements implemented at DNB.

The inspection reviewed the Written Schemes of Examination (WSE) and associated examination reports for selected systems, roles and responsibilities of key staff, process oversight and governance, I also sampled compliance arrangements against license conditions (LC) LC10 (training) and LC28 (examination, maintenance, inspection and testing) to judge the adequacy of the arrangements in place.

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

DNB was able to demonstrate that their staff had an understanding of the roles and responsibilities in relation to PSSR, that WSEs were in place for pressure systems at the station, and that systems had been created to ensure that the examination is carried out at the correct time.

I am content that PSSR Advisor and competent person were able to demonstrate the effective management of PSSR examination postponements, that the competent person is made aware of repairs or modifications to pressure systems, and that DNB is able to adequately respond to imminent danger defects raised by the competent person.

DNB was also able to demonstrate that for those systems sampled, maintenance routines exist in addition to those associated with PSSR examinations so that nuclear safety plant items can be suitably inspected to assist LC28 compliance.

However for the systems sampled during the inspection, DNB was not able to demonstrate a robust process of acting upon time related defects and recommendations contained within the competent person examination report, as required by PSSR Regulation 12 and its Approved Code of Practice. DNB acknowledged that examination reports are not currently checked by the System Engineers as required by COP/036. In addition, DNB local arrangements documentation does not reflect the responsibilities identified within PSSR or COP/036 and had not been communicated to BV.

I also identified a shortfall relating to the WSE of their Propane system. I do not consider that this shortfall necessarily represents a systematic failing of arrangements at DNB and I am aware that the propane system pipework has been inspected and refurbished as part of their pipework inspection project. However NGL and BV should address this matter in order to minimise the potential of its reoccurrence. DNB were also unable to explain the controls in place to prevent smaller, potentially portable items of pressure equipment, being put into use without a WSE.

Conclusion of Intervention

During the inspection, several areas for improvement, PSSR shortfalls and non-compliance with COP/036 were identified and communicated to DNB. In particular a significant shortfall was found against the PSSR ACOP with respect to taking into account recommendations from the reports of examination provided by the competent person, indicating that a legal requirement under PSSR Regulation 12 may not be being met. Based upon these inspection findings we judge that an Amber rating should be recorded against PSSR compliance.

A list of key findings and actions from this intervention has been provided to DNB for their consideration and resolution. One level 3 issue, number 4976, has been raised to track the progression of the actions raised during the visit and to prompt a revisit to DNB at a suitable future date.

ONR will write to DNB seeking assurance that the shortfalls identified against PSSR and COP/036 will be resolved, providing a list of key findings and actions from the intervention.

As a result of our visit, I recommend that ONR revisit DNB once the revised approaches to managing PSSR compliance have been given suitable time to become established. This should include the following:

Meet with the new PSSR Advisor and competent person once they have been in post for a suitable time.

Assess the adequacy of arrangements implemented to address the actions raised in this Intervention record and subsequent letter sent to station.