Surveillance Program - std301320000054

DOE-STD-3013-2000

plutonium metal and oxide storage packages, it is reasonable to expect that failures

would follow a pattern typified by the bathtub curve. Surveillance Programs should

1) account for the increased failure rate anticipated early in the life of the storage

package; 2) recognize the lower inherent "mid-life" failure rate; and 3) monitor for

the onset of end of life conditions.

There are at least three possible storage configurations that span the risks

associated with plutonium storage. One configuration places the storage package in

a vault that relies on the containment function of the storage package to ensure

public safety. Another places the storage package in a vault that does not rely on

the integrity of the package, and in which the primary risks involve worker safety. A

third possible storage configuration places the storage package in some sort of

container or over-pack. If the over-pack does not rely on the integrity of the storage

package, then the condition of the storage package may not be important to safety,

except as it may affect risks associated with opening the over-pack. The surveillance

program should take into account the risks associated with storage (i.e., the

consequences of failures as well as their probabilities). The program should consider

the balance between these risks and surveillance costs, both in terms of economic

impact and personnel exposure to radiation or other hazardous environments, in

determining the parameters of the surveillance program.

Finally, there are two broad classes of "problems" that surveillance is expected to

detect. The first class could be called "anomalies" because they are single events

that occur more or less randomly in a large population of storage packages. The

second class could be called "systemic" because they affect a significant fraction of

the storage packages, and generally represent an unanticipated condition in those

packages. The surveillance program is expected to be able to distinguish between

these two classes and to provide information upon which corrective or other action

can be based.

The surveillance program should document the surveillance "philosophy" in terms of

the characteristics described above. Then, it should apply that philosophy to the

specific storage situations that may be encountered. For example, in a facility that

relies on package integrity for public safety (i.e., where the container is designated

safety class") and in which the packages are easily accessed and inspected, a