The Nuclear Research and Consultancy Group (NRG) said the repair work on the cooling water pipes of the High Flux Reactor (HFR) in Petten, the Netherlands, has been successfully concluded. The return-to-service plan has been approved, and the first start-up preparation activities will take place at the end of August.
The NRG added that it is seeking to achieve the first HFR Full Power Day (45 MW) on Sept. 9. The NRG plans to prepare the sub-pile room (the space below the reactor vessel) in the next few weeks for normal operation, refilling the reactor basin with water and removing the extra radiation shielding.
After safety tests, a five-day containment test will be carried out to verify that the HFR dome is leak-tight. "The inspection team will also take a 'Zero Time Point' measurement of the repaired pipe sections. The results of this measurement will be used as the reference point for future in-service inspections”, said NRG.
There have been no safety incidents during the repair period and the radiation dose levels for internal and external employees have remained well below the planned limits, noted the group.