The lower portion of the plant would contain the reactor, its auxiliary 

 systems, shielding, the secondary system condensate and feed pumps, and the 

 freshwater cooling system. The midsection would contain the turbine genera- 

 tor and its auxiliary systems. A shield deck separates the midsection from the 

 lower compartment, through which there is limited access while the plant is 

 operating. The upper level would contain all the electrical and electronic 

 equipment, the power plant control equipment and enclosures, the primary 

 distribution equipment, and the transmission control and instrumentation 

 circuits. An air conditioning unit would be provided for temperature and 

 humidity control of the upper compartment. Cable penetrations through the 

 hull and the access hatch would be located in the upper compartment. 



An inner cylinder would be provided in the lower reactor compartment 

 to form a steam condenser. This cylinder supports nearly all the equipment in 

 the midsection and meets the hull only through a flexible skirt at the upper 

 end of the inner cylinder. The bottom end of the cylinder would be fastened 

 to the shield tank structure. This arrangement would prevent pressure hull 

 deflections from disturbing the equipment. The deck above the cylinder is 

 connected to the shield deck by stanchions. 



The inner cylinder provides a structure on which the complete plant 

 may be assembled, tested, and installed within the pressure hull without 

 disassembly. Prior to installation, the reactor operating time and power level 

 should be limited to the amount of residual radiation which would not pro- 

 hibit handling during installation. For subsequent refueling or maintenance, 

 the inner cylinder with the two deck levels may be detached and removed 

 as a unit. 



The maximum radiation levels established for the in-situ plants are 

 presented in Figure A-4. These levels would allow limited personnel access 

 to the area above the shield deck for servicing the plant while it is operating 

 at full power. Since occupancy times can only be predicted, the maximum 

 permitted radiation levels established may be lower than necessary. A pri- 

 man/ shield would be provided by lead and shield water tank. This would 

 allow limited access to the exterior of the pressure hull after the reactor is 

 shut down (30 days). Dose rates during operation would be high in the 

 water surrounding the reactor compartment. A protective screen would be 

 required around the reactor compartment at shallow depths where divers 

 may have access. 



Requirements for a special containment vessel for this power plant 

 were not firmly established. Such a vessel would protect the pressure hull 

 from overstress due to thermal gradients resulting from secondary steam, 

 primary coolant relief valve lifting, or primary coolant system leakage. The 

 containment vessel would also provide additional protection against the 



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