Reactor auxiliary systems fuel building

The CAREM nuclear island is located inside a pressure suppression containment system. The building surrounding the containment is in a single reinforced concrete foundation mat. It supports all structures with the same seismic classification in one block, allowing the integration of the RPV, the safety and reactor auxiliary systems, the fuel elements pool and other related systems. This building acts as a secondary containment. 

In the case of plants located deep in rock, the studies and the solutions implemented follow either one of the following two possibilities location of the turbine-generator system at depth close to the reactor cavern or location of this system on the surface. Indeed, the turbine-generator system is less vital to safety than the reactor, the auxiliary building and the fuel building. Figure 21-2 shows the layout of the cavern power station SENA with the turbine-generator plant located on the surface. 

The reactor auxiliary building directly adjoins the reactor building. It accommodates the facilities for helium purification and for the treatment and storage of radioactive waste, the ventilation systems, the store for new fuel elements, the sanitary rooms and other rooms such as laboratories. The central, monitored entrance to the reactor building is through the reactor auxiliary building. 

The RB is designed for a relative pressure of 0,5 bar which conservatively covers accidental pressure increase due to the evaporation of the water of the Reactor Pool. Two RB sizes are foreseen a single module size and a three modules size with common fuel element and component handling facilities. Apart from this, each module has its own dedicated auxiliary systems, of which those which process primary fluids are located in segregated areas. A separate access to each potentially contaminated area is provided from the common areas in the upper portion of the reactor building. 

All safety-grade systems in the PIUS plant are located within the reactor building which encloses the containment, the fuel handling equipment, the fresh fuel storage, the spent fuel storage pool and the emergency control room (the auxiliary shutdown facility) with associated instrumentation, control equipment and batteries for electric power supply. 

This subsection should provide relevant information on the heating, ventilation, air conditioning and cooling systems in a format as described in paras 3.65-3.70. It should include the ventilation systems for the control room area, the spent fuel pool area, the auxiliary and radioactive waste area and the turbine building (in boiling water reactors) and the ventilation systems for engineered safety features. 

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