The purpose of this intervention was to undertake planned compliance inspection activities at EDF Energy Nuclear Generation Limited’s (NGL’s) Heysham 1 power station in line with the 2017/18 Heysham 1 Integrated Intervention Strategy (IIS).
Assisted by an ONR specialist (Chemistry) inspector, I performed a system based inspection to confirm the implementation of safety claims made for the CO2 Processing and Blowdown system (NGL system codes B22 and A23 respectively). For brevity within this report, I refer to myself and the specialists views as ‘”I’ throughout. The Licence’s compliance with the following licence conditions (LCs) was examined:
In addition, I undertook the following interventions on the site:
I undertook a routine compliance inspection to evaluate the site’s LC 23 (operating rules) compliance arrangements.
I reviewed progress with ONR issue management.
I undertook information gathering discussions with station personnel including Independent Nuclear Assurance and Emergency Preparedness Engineer.
On the basis of the evidence sampled during this inspection, I judged that the CO2 Processing and Blowdown system meets the requirements of the safety case and is adequate, therefore warranting an overall assessment rating of GREEN.
Routine LC 23 (Operating rules) inspection: from the evidence sampled and the discussion held with station personnel, I consider that the arrangements sampled for compliance with LC 23 are in line with ONR guidance warranting an inspection rating of GREEN; with no regulatory issues being raised.
System-Based Inspection: Based on my sample of training records, I was satisfied staff training records and profiles were largely in accordance with the requirements for the roles performed. The exception to this related to assimilation of essential role specific training for the System Engineer, which I judged to be adequately captured by other Level 3 and 4 ONR issues. I therefore judged the LC 10 element of this inspection to be adequate, warranting an assessment rating of GREEN.
With regard to my sample for LC 23 and LC 24, I judged that technical specifications and station operating instructions were adequately aligned with claims presented within safety case. I therefore judged the LC 23 and LC 24 element of this inspection to be adequate, warranting an assessment rating of GREEN.
Availability and connection of structures, systems and components satisfying the criteria for safety mechanisms, devices and circuits was apparent based on my sample for LC 27, with EIMT records found to be in order and appropriately covered by the maintenance schedule. I therefore considered the arrangements for LC 27 to have been adequately implemented and warrant an assessment rating of GREEN.
I undertook a sample inspection of the examination, inspection, maintenance and testing regime of components which were both important and contributors to nuclear safety. Overall, the maintenance regime was judged to be adequate. The exception to this finding related to an item previously retired from the maintenance schedule. Station has appropriately captured this within an investigation and has raised an action to capture the potential wider implications. I therefore consider that an assessment rating of GREEN appropriate against LC 28.
From an LC 34 perspective, Station was actively identifying and managing leaks within the system. Additionally, a contractor-performed LC 34 review appeared to appropriately consider the detection and preventative maintenance required for radioactive leaks. I therefore judge an assessment rating of GREEN to be warranted.
The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.
After considering the evidence examined during the inspections undertaken against LCs 10, 23, 24, 27 28, and 34, I considered that the CO2 Processing and Blowdown system meets the requirements of the safety case. A number of minor observations were raised during the inspection, which are being tracked by an ONR issue or appropriate Licensee actions.
There are no findings from this inspection that could significantly undermine nuclear safety and no change to the planned interventions and inspections of Heysham 1.