The purpose of this intervention was to undertake a system based inspection of the reactor safety system trip parameters at EDF Nuclear Generation Limited’s (NGL’s) Heysham 2 power station in line with the planned inspection programme contained in the Heysham 2 Integrated Intervention Strategy (IIS) for 2015/16.
As part of this intervention, the ONR Nominated Site Inspector and a C&I Specialist Inspector performed a System Based Inspection (SBI) of the reactor safety system trip parameters to judge the system performance against its safety function. Through examination of this system and associated sub-systems we performed compliance inspections against Licence Conditions LC10 (Training), LC23 (Operating rules), LC24 (Operating instructions), LC27 (Safety mechanisms, devices and circuits) and LC28 (Examination, inspection, maintenance and testing). LC34 that relates to leakage and escape of radioactive material and waste and was considered not applicable to the reactor safety system trip parameters.
From the inspection, we judge that overall the reactor safety system trip parameters meets the requirements of the safety case and is adequate.
During the course of the system inspection it was found that Heysham 2 has adequate arrangements to ensure that the reactor safety system trip parameters are maintained and operated in accordance with the safety case and the station’s arrangements, based on the areas sampled by the inspection.
In summary, the outcome from the SBI of the reactor safety system trip parameters was:
The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.
After considering all the evidence examined during the sample inspection undertaken against LCs 10, 23, 24, 27 and 28, we considered that the requirements of the safety case have been adequately implemented at Heysham 2.
There are no findings from this inspection that could significantly undermine nuclear safety. At present, no additional regulatory action is needed over and above the planned interventions of Heysham 2 power station as set out in the Integrated Intervention Strategy, which will continue as planned.