- 51 - RHF The inspectors found that the current frame of reference in force was adhered to. They did however note that a reassessment of the flood hazard was underway, as the current design of the facility was insufficient to deal with the consequences of the submersion wave that would result from the various Monteynard dam burst scenarios. Without in any way pre-judging the discharge and level adopted following this reassessment, which is to appear in the updated safety report planned for 2012, the inspectors observed that the fall-back centre, the backup electricity generators, the batteries and the doors of the reactor building were currently designed for a water level of 210.5m NGF. Above this level, they are vulnerable to the risk of flooding. With regard to the emergency response resources, these are defined in the PUI and in a special operating instruction on "what to do in the event of flooding". However, the list given in these documents will need to be checked and updated, especially with regard to the pumping resources available on the BNI. It should also be pointed out that a motor-driven pump could also be made available to the RHF by CEA in Grenoble. The procedures for using and transporting this motor-driven pump need to be defined, particularly for a scenario in which CEA is also flooded and might also need it. The normal and emergency pumping resources appeared to be in good condition. However, certain flood door seals were found to be in poor condition and the closures on openings also need to be refurbished. Phénix The inspectors found that the ventilation system was not seismic qualified and that the availability of the resources for measuring and sampling the radioactive gas discharges could not be guaranteed in case of Maximum Historically Probable Earthquake (MHPE) type earthquake. They thus asked that the necessary steps be taken and justifications provided. 3.2.2 Nuclear fuel cycle facilities La Hague site The flood risk at La Hague would stem from heavy rainfall and the presence of groundwater under the facilities. The main observations made during the inspections and the additional requests are presented below. Examination of the frame of reference showed the following discrepancies: inconsistency in the management of a degraded situation in certain operating instructions, depending on the heavy rainfall typology and the absence of any measures to compensate for unavailability of the sump level sensor. Furthermore, it would seem that the personnel's specific flood risk training is today insufficient. The inspectors asked for a general earthquake or flooding exercise to be held on the site. An exercise such as this has not yet ever been organised. The inspectors also identified additional measures to take account of experience feedback from a 2006 event in order to check the availability of the groundwater raising systems for the semi-buried facilities (44 pits). They thus requested a study on the risk of malfunction of the groundwater raising pumps if the water to be pumped comprises large quantities of suspended particles, as a result of earthquake or flooding. The inspection found two occasions of damaged waterproof covering on the building roofs. The inspectors also looked at the question of the durability of the watertightness (PVC) of the buried facility basemats. This problem is in principle not included in the monitoring programme. Certain electrical cables needed for the backup functions are also buried in trenches. The watertightness of these cables in immersion conditions needs to be demonstrated. To conclude, the inspectors noted relative susceptibility of the buried facilities to the risk of flooding, with corrective measures required on the means of pumping the groundwater (availability monitoring to be improved, modifications to be made). They asked that a study be conducted on the continued functioning of the pumping resources if the water were to contain particles in suspension. The observations also showed that monitoring of the maintained integrity of the civil engineering watertightness systems needs to be improved. The qualification of certain electrical equipment
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