22 Sep 2021

Current status in decommissioning of V1 NPP primary circuit contaminated components

Fragmentation of Steam Generator heat echange tubes © JAVYS,a.s.
Fragmentation of Steam Generator heat echange tubes © JAVYS,a.s.

The large contaminated components, being in the scope of Slovak company VUJE are continuously dismantled and fragmented to the fragments with mass less than 1 ton within the separate workshops or workplaces enables the application of additional measures (e.g. construction barriers, local ventilation systems, limited access of workers, measures for avoiding the potential leakages of radioactivity) to increase the safety level (including radiation protection) of decommissioning activities and to minimize the amount of produced radioactive waste. The current status of dismantling and fragmentation of large contaminated components is as follows: 

  • Steam Generators - (12 pieces) are fragmented in the dry cutting workshop constructed in the premises of Turbine Hall. The shell of the SGs is fragmented separately from the heat-exchange tubes and primary collectors. Currently, the fragmentation of seventh Steam Generator is in progress. 
  • Pressurizers together with Pressurizer Relief Tanks (1 per each unit) - both components were in-situ fragmented by using wire saw cutting as well as thermal cutting methods. Fragmentation of both Pressurisers as well as Relief Tanks was successfully completed in 2020. 
  • Primary piping – after tag-out from other primary circuit components, the primary pipping was removed (cuts were done by orbital saw) and successfully fragmented by using a large band saw during the years 2019 and 2020. 
  • Main Circulation Pumps (12 pieces) and Main Isolation Valves (24 pieces) – two dry cutting workshops with wire saw and large band saw were established in the hermetic areas. The fragmentation of both components is expected to be completed in autumn 2021. 

Moreover, the dismantling and fragmentation of large extent of auxiliary systems and components within the hermetic area is being continuously performed.


Matej Zachar