Packaging Process - std3028

DOE-STD-3028-2000

2. The assurance of safe storage embodied in this Standard rests on the defense-in-

depth premise that there are two barriers (containers) that are each capable of

withstanding credible pressure, corrosion, etc. In the case of pressurization, this is

accomplished by ensuring that the design pressure of the container is greater than

the theoretical ability of the contained materials to pressurize, as determined by the

bounding pressure calculation derived in Appendix B.

3. Using the lowest of multiple limits is the most conservative approach.

A.6.3.3

Packaging Process

1. Foreign materials such as metal items and processing debris are not expected in

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U oxide packages. Any such materials shall be removed from the oxide prior to

packaging. Items may be removed manually or by screening the powder, and can be

removed either before or after stabilization.

2. Because the oxide (including contained impurities) may pick up atmospheric water, it

is important that the sample taken for volatiles analysis be representative of the

material actually packaged into the storage container. This can be done, for

example, by controlling the glovebox atmosphere and/or packaging within a very few

minutes of sampling.

3. This Standard prohibits packaging materials that may corrode the containment

system. The primary corrosion mechanisms of interest are general corrosion and

stress corrosion cracking. A recent evaluation of both types of corrosion using PuO2

concludes that neither of these mechanisms is likely to be significant under storage

environments anticipated by this Standard. [Kolman, 1999]

General corrosion is not a credible problem because the quantity of oxidizer (oxygen

or water) available to react with the containers is too limited to be significant. The

initial amount of elemental oxygen available if an air atmosphere was present during

packaging is very small, and little elemental oxygen is expected to result from

catalytic or radiolytic decomposition of water (see Section A.6.1.2 of this appendix).

This also makes corrosion pitting highly unlikely.

4. To promote material homogeneity for facilitating MC&A measurements and

stabilization tests (such as for adsorbed residual volatiles), and to preserve