On 30 March 2018, a meeting of the Board of the State Nuclear Regulatory Inspectorate of Ukraine was held. The meeting was held to consider the results from investigations of operational events and occurrences at national NPPs and calculations of safety performance indicators for 2017. The agenda also included the topic on progress of the ZNPP-4 long-term operation activities.
The meeting was opened by SNRIU Chairman Hryhorii Plachkov. He emphasized urgency of the issues under consideration for nuclear and radiation safety of the country.
“I would like to remind that the issue on efficiency of using operating experience, results of event and occurrence investigation at NPPs from 2015 to November 2017 was considered by the SNRIU Board not long ago: in 30 November 2017. The investigation of certain events were not completed, in addition, until the end of the year, several events took place. Thus, today, we have the opportunity to hear the information on the status of implementing the Board’s decision and to consider in detail causes of events and results of event and occurrence investigations at NPPs. The investigation of events and occurrences at NPP is under thorough control and as a state regulatory body for nuclear and radiation safety, the SNRIU is guided by the requirements of national standards for nuclear and radiation safety and international recommendations”, Hryhorii Plachkov said.
During the consideration of the results of event and occurrence investigation at NPP, it was noted:
– in 2017, 17 events at NPPs of Ukraine occurred, which is the largest number during the last 7 years. However, when considering statistical data on the total number of NPP operational events in Ukraine (events and occurrences) a positive trend was defined: decrease in their total number during the last three years;
– during 2008-2017, there were no events at Ukrainian NPPs resulting in the exposure of personnel or release/discharge of radioactive substances to the environment above the regulated values. Over the last 5 years, all NPP operational events have been rated as “below the scale/level 0” (not significant to safety) according to the International Nuclear and Radiological Events Scale (INES).
Summing up the issue consideration, the Board emphasized the importance of ensuring efficient functioning of the operating experience feedback system (experience in investigating NPP operational events) as one of the components of NPP safety.
SNRIU Chairman Hryhorii Plachkov
The second issue of the agenda is the status of implementing activities on ZNPP-4 long-term operation.
The design lifetime of ZNPP-4 expires on 4 April 2018. The operating organization submitted a set of documents on the operation of this unit in shut down state for the period of implementing necessary organizational and technical measures to justify the possibility of its long-term operation.
Having heard the speeches of representatives of ZNPP “On ZNPP-4 preparedness for long-term operation”, State Scientific and Technical Center for Nuclear and Radiation Safety “Results of the expert review of the periodic Safety Review Report of ZNPP-4” and State Nuclear Regulatory Inspectorate of Ukraine “On the results of considering the application to amend SNRIU license and preparedness state of ZNPP-4 for long-term operation” the Board decided the following.
As of 30 March 2018, the Energoatom justified the possibility of ZNPP-4 long-term operation only in shutdown state with nuclear fuel unloaded from the reactor core.
Consider possible addressing the issue on operation renewal for this power unit at power levels after full implementation of a number of measures, in particular:
– Completion of development taking into account the state review on nuclear and radiation safety, Periodic Safety Review Report.
– Lifetime extension of the reactor pressure vessel, primary equipment, pumping equipment. etc.
– Seismic resistance assessment for equipment and piping.
– Equipment qualification for rigid environmental conditions and seismic impact.
– Implementation of the measures of the Comprehensive (Integrated) Safety Improvement Program for NPP units.
According to SNRIU