Office for Nuclear Regulation

Heysham 2 Power Station – Licence Condition Compliance Inspection of LC14, LC22, LC27, and LC28

Executive summary

Purpose of intervention

The purpose of this intervention was to undertake a Licence Condition (LC) compliance inspection at EDF Energy Nuclear Generation Limited (NGL) Heysham 2 power station in line with the planned inspection programme contained in the Heysham 2 Integrated Intervention Strategy (IIS).

Interventions Carried Out by ONR

This intervention included compliance inspections against the following Licence Conditions (LC):

The inspection undertaken utilised the following ONR guidance documents:

These guidance documents require inspectors undertaking compliance inspections against these LCs to consider both the arrangements that are in place together with their associated implementation.

The intervention was undertaken as a joint inspection with the incoming Heysham 2 Nominated Site Inspector. 

Explanation of Judgement if Safety System Not Judged to be Adequate

No safety system inspection was undertaken, hence this is not applicable.

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

For LC14 we sampled into arrangements and implementation in relation to individual safety case author competence, categorisation and the application of due process to safety case production, safety case ownership, and operational experience.  Based on the evidence sampled during this inspection, I consider that NGL are actively seeking to improve and learn from the work they perform in this area and believe this to be a positive element of the approach taken by NGL in the production, review, approval, and implementation of safety cases across Heysham 2.  As a result I have rated this element of my inspection through the IIS as 2 (good).

For LC22 we followed up on the NGL investigation into an event relating to modifications made to a start/standby boiler feed pump (SSBFP) further to my inspection performed in December 2014 as well as considered quality assurance arrangements and contract specifications for modifications performed on plant.  We also sampled a recent modification to ensure implementation in accordance with the arrangements in place. 

I was content that Heysham 2 had performed a thorough and robust investigation into the SSBFP event and had taken action to mitigate against potential future re-occurrence.  As a result of the findings of my inspection into this event, I am content to close the ONR Issue raised in December 2014.  I was satisfied with the implementation of the arrangements associated with quality assurance and contract specifications and considered the identification of opportunities for improvement by NGL to be positive.  There were some minor observations associated with the implementation of the safety case sampled associated with ammonia dosing protection systems, which station are to address, however, I have raised an ONR Issue for NGL to respond within appropriate timescales.  Based on the evidence sampled during the inspection, I have rated this element of my inspection through the IIS as 3 (adequate).

For LC27 NGL explained that they were in the process of implementing arrangements to clarify their approach to the identification of safety mechanisms, devices and circuits across the NGL fleet.  This involves linking a number of licence conditions, namely, LC23, 24, and 28 to provide the requisite detail in order to comply with LC27 and is to be captured within an update to BEG/SPEC/SHE/008.  Recognising that this is ongoing work involving ONR and NGL we elected not to sample further into this area.  However, we did consider LC27 as part of the wider arrangements through the LC28 inspection as well as during the plant walkdown in relation to barriers and plant locking.

No safety shortfalls arose during the plant inspection in relation to LC27 in that all the barriers inspected were confirmed to be intact and meeting the requirements of the internal hazards safety case.  Plant locking was subject to sampling inspection also and observed to be consistent and in accordance with the requirements of the NGL arrangements in this area.  Based on the evidence sampled during the inspection, I have rated this element of my inspection through the IIS as 3 (adequate).

For LC28 we sampled the arrangements and implementation in the areas of equipment reliability, trending and condition monitoring, maintenance schedule defects and event notification under Licence Condition 7 (Incidents on the site).  In addition we considered the arrangements in place in relation to the acquisition of goods and services and item equivalency in relation to replacement plant items and spares.  We also performed a plant sample of maintenance for the quadrant excess drainage system as well as the replacement conductivity transmitters.

We considered the approach taken to the proactive preventative maintenance performed at Heysham 2 to be comprehensive and robust and did not identify any shortfalls or areas for improvement with the approach adopted.  In addition, we were satisfied with the implementation of the arrangements associated with notification of incidents under LC7 as well as from the sample of maintenance performed arising from the plant inspection.  Based on the evidence sampled during the inspection, I have rated this element of my inspection through the IIS as 3 (adequate).   

The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.

Conclusion of Intervention

Overall I considered that the arrangements and their associated implementation for all Licence Conditions inspected met the requirements of ONR guidance.  I have rated the LC14 element of my inspection through the IIS as 2 (good) and the remainder as 3 (adequate). 

There are no findings from this inspection that could significantly undermine nuclear safety and no change to the planned interventions and inspections of Heysham 2.