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Belgian stress tests action plan ‐ 2012‐12‐14No Topic Source Recommendations, Requirements from other national reviews Action : Family ‐ subfamily ‐ sub‐subfamilyActions to beimplementedComment41Design issuesNational regulatoryinspectionSpent fuel poolsTwo configurations should be evaluated by the licensee for the spent fuelpools:∙ Configuration with a fuel assembly handled in the reactor pool during a “TotalSBO”. The fuel assembly should manually be handled in a safe position. Thelicensee should investigate the provisions (hardware installations, procedures,lighting, etc.) to be implemented for this configuration.∙ Configuration with the loss of water inventory in the spent fuel pools. Theinternational experience feedback has already pointed out potential problemswith the design of the siphon breakers in the spent fuel pools. In case of pipingrupture, an insufficient capacity of the siphon breakers may lead to a fastuncovering of spent fuel assemblies. The licensee should examine this safetyconcern.Power supply ‐ Total Station Black‐out ‐ Safe PositionFuel AssemblyWater supply ‐ Total Station Black‐out ‐ Inadvertentlet down of the pools456, 500, 555, 556§ 7.2.4 of national stresstests report43Emergencypreparedness andresponseNational regulatoryinspectionSevere accident managementThe adequacy of the procedural guidelines (BK procedures for Doel and severeaccident management guidelines for Tihange) to cope with a severe accidenthas been assessed by the licensee, relying mainly on the fact that thoseprocedures are inspired from the Westinghouse owners group severe accidentmanagement guidelines (“WOG SAMG”), are regularly updated, and arevalidated in the framework of the ten‐yearly periodic safety reviews. Yet, thoseprocedures still need to be improved with respect to the following aspects:∙ the Doel BK procedures should be supplemented with long term monitoringand exit guidelines, such as those already existing for Tihange (SAEG‐1 andSAEG‐2);Severe Accidents management ‐ Review SAMGprocedures ‐ Coherence severe accidents proceduresbetween Doel and Tihange519, 520§ 7.2.5 of national stresstests report44Emergencypreparedness andresponseNational regulatoryinspection∙ in some Doel BK procedures, reference is made to (the distinct) FRGprocedures for the explanation of recommended methods. This constantswitching between different procedures should be avoided, and therefore theBK procedures should be more selfsupporting and contain all informationneeded for their application;Severe Accidents management ‐ Review SAMGprocedures ‐ Coherence severe accidents proceduresbetween Doel and Tihange519, 520§ 7.2.5 of national stresstests report45Emergencypreparedness andresponseNational regulatoryinspection∙ an in‐containment pH calculation tool should be added to the BK/SAMGprocedures to determine the sump water acidity from the volumes and waterquantities used during the management of the accident, taking into account allother physical and chemical pH influencing processes; this tool would also beused as a check and back‐up for a dedicated sampling system;Severe Accidents management ‐ Radiological release ‐pH reactor control396, 527, 608, 620§ 7.2.5 of national stresstests report46Emergencypreparedness andresponseNational regulatoryinspection∙ a decision support tool (table/flow chart) should be added to the BK/SAMGprocedures to quickly pinpoint the (most probable) location of a containmentleak path based on the readings of certain detectors and to determine the mostappropriate actions to limit the spread of fission products. This approach mightinvolve the deployment of mobile detectors at specified locations;Severe Accidents management ‐ Radiological release ‐Leak path identification392, 523, 524§ 7.2.5 of national stresstests reportAdditional topics7/9