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
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