Design Considerations cont'd

DOE-HDBK-1132-99

confirmation. The design of the vault system should facilitate inventory

requirements. Those areas of the facility where SNM is stored should be

located in the least accessible area of the plant.

To expedite recovery from accidents and provide facility versatility, modular

construction concepts should be used, where feasible.

No hazardous gases or liquids should be used in UEUSFs. No natural gas for

heating purposes should be used unless the heating occurs in a separate

building that is clearly isolated from the primary facility.

New storage facilities should be physically separated from process operations,

storage of nonnuclear materials or equipment, and functions not directly required

for storage operations.

Combustible packaging materials should be stored in metal containers or

structures outside a UEUSF in a location that should not endanger the storage

facility or stored material should a fire occur in the packaging material. The need

to provide automatic fire suppression systems for these areas should be

considered.

Facility layout should provide for efficient cleaning, maintenance, and ease of

inspection. Layout of floor and access areas should consider the requirements

for secure location of storage containers, traffic control, and segregation.

Suitable physical compartmentalization should be considered to limit the quantity

of stored materials in each compartment to safe levels, to provide the necessary

access features and controls, and to satisfy loss limitation criteria. Bumpers

should be provided where necessary to minimize potential damage to the

structure or racks from handling equipment.

Design of storage tanks for aqueous solutions of enriched uranium should

ensure that they are geometrically favorable with respect to nuclear criticality

safety. When there is a tendency for solids to precipitate, vessels should be

instrumented to detect the build-up of solids and designed to facilitate removal of

solids.

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