Design Considerations cont'd

DOE-HDBK-1132-99

The design should also consider the inclusion of filters capable of being

either remotely back-flushed or designed so that cartridges can be

removed directly into a shielded container. Instrumentation for periodic

functional testing of the pool-water cleanup system and heat-exchanger

performance should be considered. The design should use containerized

or modularized filters to reduce exposure during maintenance. Filter

change-out prior to build-up of radiation levels should be considered.

The normal water level of the storage pool should be at or near the final

design grade level. The water level necessary for in-storage radiation

shielding should be at or below grade.

For water-pool type facilities, the design professional should consider

providing the pool liner with a leakage collection system that will allow

leakage detection and limit absorption of contaminated pool water by

concrete structures.

A system should be incorporated to detect leakage from stored IFM in the

event of a cladding or canning failure that could allow the escape of

fission products and other radioactive material greater than specified

limits. This system should include the following:

Sampling of coolant allows identification of an individual leaking

assembly.

System components, piping, and instrumentation are appropriately

shielded to maintain operator exposures within guidelines and use

ALARA design principles to minimize overall exposures.

The storage facility provides for the temporary storage of a leaky

assembly. These provisions should limit the spread of

contamination by a leaky assembly and provide adequate cooling

and shielding of the assembly.

I-67