The purpose of this intervention was to carry out a compliance inspection and attend routine meetings at EDF Energy Nuclear Generation Limited’s (NGL’s) Heysham 1 power station in line with the planned inspection programme contained in the Heysham 1 Integrated Intervention Strategy (IIS) for 2015/16.
I, the ONR nominated site inspector, and a civil engineering specialist inspector carried out a planned LC22 – modification or experiment on existing plant, compliance inspection. I also reviewed progress against the Improvement Notice issued on the East Carbon Dioxide (CO2) plant as well as attending the routine biannual Local Community Liaison Committee (LCLC).
Not applicable during this intervention.
Prior to this inspection, I carried out a review of the company LC22 procedures against the relevant ONR guidance documents for this licence condition. I judged that these procedures provide adequate arrangements to satisfy the requirements of LC22.
In order to determine the adequacy of the implementation of these arrangements, I reviewed the recent modifications to the Direct Contact (DC) heaters. There is a bank of DC heaters for each reactor at Heysham 1 and their purpose is to improve the efficiency of the secondary circuit heat transfer by bleeding some of the steam from the low pressure turbine to heat the condensate which will then become boiler feed water.
Although the modifications have been designed and approved by suitable qualified and experienced persons, only hand written drawings of the modifications were available. These were not judged to be suitable and sufficient technical drawings. To confirm the adequacy of these modifications, the station undertakes routine inspections. However I judged that the inspection records did not contain sufficient detail to allow appropriate decision making to be undertaken. An issue has been raised on the station to address these shortcomings.
In light of the findings from this inspection I consider that compliance with LC22 is below standard with an IIS rating of 4.
I reviewed the stations Improvement Notice close out report, which presented the rationale and the scope of inspection and remedial maintenance undertaken, the revised maintenance policy for the East and West CO2 plant, and the document matrix which provided a route map to the remedial work undertaken, the maintenance records and other relevant documentation. I also sampled sections of the CO2 plant against these documents to determine the adequacy of the work undertake.
I judged that the work undertaken to address the Improvement Notice is to a good standard and therefore I have rated this reactive intervention against LC28 as good with an IIS rating of 2. I reiterated the comments made in the original covering letter to the Improvement Notice that the lessons learnt from this work should be rolled out across the station and the rest of the AGR fleet.
As a result of this inspection I consider that the station has met the requirements of the Improvement Notice and I advised them that I would be writing to them separately to confirm this. I also noted that all CO2 pipework is now included on the maintenance schedule. This addresses a previous ONR issue which will be closed accordingly.
I also attended the LCLC where both Heysham 1 and Heysham 2 presented an update on their safety performance since the last meeting to the local community. ONR presented the quarterly report for both stations and no questions were raised on the report by the LCLC members.
The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.
From the evidence gathered during this intervention, I do not consider there to be any matters that have the potential to impact significantly on nuclear safety.
At present, no additional regulatory action is needed over and above the planned interventions of Heysham 1 power station as set out in the Integrated Intervention Strategy, which will continue as planned.