The purpose of this intervention was to carry out licence compliance inspections at the EDF Energy Nuclear Generation Limited's (NGL's) Heysham 1 and Heysham 2 power stations and attend some routine meetings in line with the planned inspection programme contained in the Heysham 1 and Heysham 2 Integrated Intervention Strategy (IIS) for 2016/17.
As the nominated site inspector I carried out Licence Conditions (LC) 2 - marking of the site boundary and LC16 - site plans, designs and specifications compliance inspections on both the Heysham 1 and Heysham 2 nuclear licensed sites. I was joined by a security inspector during these inspections. I also carried out follow up enquiries on Heysham 1 to a defect identified during a Lifting Operations and Lifting Equipment Regulations 1998 (LOLER) examination. Separately, I attended the Heysham 1 Annual Review of Safety (ARoS) with the ONR delivery lead for operating reactors and attended a routine meeting with the Heysham 1 station safety representatives. I was also in attendance on site during the declaration of a site incident on both sites.
No safety system inspection was undertaken, hence this is not applicable.
At the ARoS the station provided a comprehensive review of safety over the past 12 months and the key challenges and safety improvements implemented over that period as well as a forward look. ONR acknowledged the safety improvements which have been implemented on the station; in particular the procurement of a new reserve feed tank and bulk oil tank. ONR also noted the improvement in safety culture across the site.
A review of the company procedures for compliance with LC2 and LC16 on both stations was undertaken prior to this inspection and no major deficiencies were identified. To judge the implementation of these arrangements I walked the entire Heysham site boundary along with the ONR site security inspector. Although no major deficiencies were identified, a number of the site boundary signs were not placed correctly in accordance with the site plan. The station has raised a condition report to address these minor deficiencies which ONR will monitor as part of normal business. A low level regulatory issue (ONR issues 5001 and 5002) has also been raised on each station to improve their local arrangements for compliance with LC16.
Notwithstanding these minor deficiencies, overall I judge that compliance with LC2 and LC16 meets the required standard and therefore IIS ratings of green will be recorded against these licence conditions on both stations.
On Tuesday 6 December a site incident was declared on both stations following the discovery of localised elevated levels of hydrogen within the Heysham 2 turbine hall. All staff responded in accordance with their emergency response arrangements and all staff were accounted for promptly. No persons were injured and there was no release of radioactive material. I was on site with two ONR specialist inspectors and we attended the emergency control centres on both Heysham 1 and Heysham 2. Both stations responded very well to the event in accordance with their emergency response arrangements. The station is undertaking an investigation to determine the cause of the high hydrogen levels. The Heysham 2 site inspector will follow up any lessons learnt from NGL's internal investigation as part of normal business.
I conducted followed up enquiries on a defect identified during a Lifting Operations and Lifting Equipment Regulations (LOLER) inspection by Bureau Veritas (BV). This defect notification was against the sea water cooling inlet trash baskets and had not been acted upon by the station and the lifting equipment continued to be used. This was identified by the station themselves and one of the baskets was promptly modified with station temporary lifting equipment. The remaining basket has been embargoed until the appropriate repairs have been undertaken.
Prior to me leaving the site the station confirmed that there were no other adverse LOLER defects that have been identified by BV which have not been addressed or are in the process of being addressed with the relevant equipment embargoed until the defects have been addressed. In addition the station has produced a draft recovery plan to prevent a reoccurance, with a commitment to present a more detailed plan with associated timescales by the end of the year.
Given that no persons were injured and the station has taken prompt action to address this non-compliance, I judge that there was not an immediate or imminent risk of serious personnel injury and therefore no immediate action was required by ONR. However, in line with the ONR enforcement policy I will consider whether any formal regulatory action is required in accordance with the ONR guidance. This will be reported separately and the conclusion recorded in an ONR decision note. In light of this non-compliance with LOLER I will rate this reactive intervention as an IIS rating of red.
I also attended a routine meeting with the station safety representatives to discuss any safety concerns that the staff had around the station and to feedback the findings from my previous interventions at the station. No significant safety concerns were raised.
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.
The consideration of any additional regulatory action with respect to the non-compliance with LOLER will be considered separately in accordance with ONR enforcement policy and associated guidance. The remainder of the planned interventions of Heysham 1 power station as set out in the Integrated Intervention Strategy, will continue as planned