Heysham 2 - LC11 and LC12 Inspections - SBI16
- Site: Heysham 2
- IR number: 17-025
- Date: May 2017
- LC numbers: 10, 23, 24, 27, 28, 34
Purpose of Intervention
This was a planned inspection of EDF Energy Nuclear Generation Ltd's (EDF-NGL's) Heysham 2 Power Station, undertaken as part of the planned intervention strategy for the Operating Facilities Division (OFD) of the Office for Nuclear Regulation (ONR).
The work was carried out in-line with the planned inspection programme contained in the Heysham 2 Integrated Intervention Strategy (IIS) 2017-2018.
Interventions Carried Out by ONR
I (the nominated site inspector for Heysham 2) with support from an ONR mechanical engineering inspector:
- carried out a Licence Condition 12 (LC12) compliance inspection of duly authorised and other suitably qualified and experienced persons;
- carried out a system based inspection (SBI) of the Irradiated Fuel Dismantling (IFD) facility including the Plug Unit Service Bay (PUSB) - referred to by EDF-NGL as the Maintenance Cell; and
- carried out a Licence Condition 11 (LC11) compliance inspection of emergency arrangements.
The nuclear site licence conditions are applicable provisions under the Energy Act 2013.
Explanation of Judgement if Safety System Not Judged to be Adequate
From our inspection, we judged that overall the IFD and Maintenance Cell system met the requirements of the safety case.
Key Findings, Inspector's Opinions and Reasons for Judgements Made
The following provides a summary of the findings and reasoning for judgments made within the above compliance inspections.
For the LC 12 (duly authorised and other suitably qualified and experienced persons) inspection - the inspection was not undertaken as the licensee had failed to make arrangements to provide individuals to participate in the inspection due to a miscommunication between individuals at the station regarding the inspection date. The site inspector stated that he would rearrange the inspection at a later date to coincide with another compliance inspection; the inspection has therefore been unrated for this intervention report.
The system based inspection, carried out on the IFD and Maintenance Cell facility covered six License Conditions (LCs). For the SBI, we concluded that:
- LC 10 (training) - we examined the role profiles of the system engineers and training records for these and three other persons, including one contractor. We noted that two individuals were overdue an element of re-training for their role, however they were enrolled on a future course. The Group Head explained that the individuals had significant knowledge and experience of the safety systems and provided a written justification as to why he felt the individuals were competent to carry out their roles. We judged this to be a relatively minor deficiency in compliance with arrangements. Therefore we assigned a rating of Green for LC 10 compliance.
- LC 23 (operating rules) - following an inspection of technical specifications, commentary and surveillance requirements we judged that the operating rules adequately reflected the limits and conditions for operation (LCOs) identified within the safety case. We therefore assigned a rating of Green for LC 23 as no significant shortfalls were found.
- LC 24 (operating instructions) - upon sampling a number of station operating instructions and maintenance instructions, there was adequate demonstration of the links from the technical specifications. One minor non-compliance was identified concerning a maintenance schedule source requirements document, however this was dealt with by the system engineer raising a condition report (CR). This enabled the error to be rectified through the stations own arrangements rather than a formal ONR issue. We also sampled reports into defects and found these to adequately meet the stations arrangements. Consequently we judged a rating of Green for LC 24 was appropriate as only relatively minor deficiencies in compliance arrangements were found.
- LC 27 (safety mechanisms, devices and circuits) - we examined a number of areas relating to limits, conditions, examination, inspection, maintenance, testing, operation and maintenance procedures for a sample of interlocks that were agreed as safety mechanisms. We also held discussions with the system engineers and fuel route engineer in regards to the defeat of interlocks. The station's arrangements for LC 27 compliance are covered within its LC 23, LC24 and LC 28 arrangements and so those aspects informed our inspection rating. Although we did find that storage of defeat of interlock documentation was not in-line with the licensee's own arrangements, a rating of Green for LC 27 was judged appropriate as we found this to be a minor failure to implement arrangements.
- LC 28 (examination, inspection, maintenance and testing) - we examined the station's maintenance arrangements and the link between the safety case and the frequency of maintenance performed. We found these to be in accordance with the licensee's own arrangements, and in line with our expectations. There was a clear link between the safety case and the maintenance tasks sampled, with appropriate instructions and records. We also found that the station was implementing what was seen as improvements in maintenance towards components not identified within the safety case as important to safety. This is believed by station to provide improved system performance. We identified this as an example of good practice, where improvements to maintenance activities were being made. Although the licensee provided evidence that plant walkdowns were being conducted, we found that the licensee was not adequately implementing the NGL procedure for plant walkdowns as per its arrangements. Time and resource pressures were identified as key factors in this non-compliance with arrangements, predominantly due to resources being required to carry out corrective actions on ageing plant. The non-compliance with procedures issue has been raised as Level 4 ONR Issue 5420 and will be progressed by the nominated site inspector. Despite the identified Level 4 issue, we judged that a rating of Green was appropriate for LC 28 as only relatively minor deficiencies in compliance arrangements were found.
- LC 34 (leakage and escape of radioactive material and radioactive waste) - We sampled the boronated water flooding system as availability is a pre-requisite to operations at the IFD. We sampled the means by which contamination from filters is prevented from escaping into the boronated water following initiation. The application of arrangements concerning operations and maintenance associated with containment of radioactive material was judged to be adequate. Therefore a rating of Green was appropriate for LC 34 as no significant shortfalls in delivery of safety were found.
- For the LC 11 (emergency arrangements) inspection - The main purpose of this intervention was to undertake a joint review of the Heysham on-site EP&R capability maps by ONR CNS, Heysham 1 and Heysham 2 site inspectors. A number of improvements have been captured in the Heysham plan and NGL has committed to update and review the Heysham capability maps again in the third quarter of 2017. A number of actions were raised, which shall be followed up through regular, planned interventions. Consequently, we have rated this intervention as Green.
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
There were no findings, from the inspections carried out, that could significantly undermine nuclear safety. An ONR Level 4 Issue (No. 5420) was raised concerning the planning and delivery of plant walk downs, which will be pursued under normal regulatory business by the nominated site inspector. At present, no additional regulatory action is required, over and above the planned interventions at Heysham 2 power station within the Integrated Intervention Strategy.