Information Notice No. 96-63: Potential Safety Issue Regarding the Shipment of Fissile Material

                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                             WASHINGTON, DC 20555

                               December 5, 1996

                              FISSILE MATERIAL


All U.S. Nuclear Regulatory Commission licensees authorized to possess special
nuclear material in unsealed quantities greater than a critical mass.


The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to alert addressees to an issue with potential safety significance
regarding shipments using the fissile material exemption provisions and
general licenses.  It is expected that recipients will review this information
for applicability to their facilities and consider actions, as appropriate, to
avoid similar problems.  However, suggestions contained in this information
notice are not NRC requirements; therefore, no specific action nor written
response is required.

Description of Circumstances

An NRC licensee recently informed NRC of a potential situation where one of
the fissile material exemptions in 10 CFR 71.53 would not have provided
adequate criticality safety if large amounts of an exempt concentration of
fissile material were to be transported in the presence of a special
moderating material (i.e., beryllium).  A recent contract was awarded to the
licensee to process weapons-usable enriched uranium materials.  The waste
product, a uranium-beryllium filtercake, met the fissile exemption provisions
in 10 CFR 71.53 and  49 CFR 173.453.  The presence of beryllium in significant
quantities in NRC-regulated fissile exempt shipments is extraordinary, and was
not considered in the development of the fissile exemptions in the
regulations.  NRC has reviewed and verified the licensee�s calculations, and
has concluded that the current regulations need to be revised to preclude
criticality in fissile exempt shipments made under 10 CFR 71.53, and fissile
shipments made under the general licenses in 10 CFR 71.18 and 10 CFR 71.22. 
This information notice is being issued to provide additional, timely notice,
to licensees, of this potential safety issue, while the regulatory revisions
are made.


The licensee proposed to employ the provision in 10 CFR 71.53(d), or the
parallel provision in the U.S. Department of Transportation (DOT) regulations,
49 CFR 173.453(d).   

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Section 71.53(d) exempts fissile material from the requirements in 10 CFR
71.55 and 71.59 (i.e., the additional requirements placed on fissile packages
and shipments to preclude 
criticality), provided the package does not contain more than  5 grams (0.18
ounces) of fissile material in any 10-liter (610-cubic-inch) volume.  The
fissile exemptions appearing in 10 CFR 71.53 are assumed to provide inherent
criticality control for all practical cases in which fissile materials exist
at or below the applicable regulatory limits (i.e., independent calculations
would generally not be expected nor required).  Consequently, the fissile
exemptions generally do not place limits on the types of moderating or
reflecting material
present in fissile exempt packages, nor the number of fissile exempt packages
that can be shipped in a single consignment, and do not require that a
transport index (see 10 CFR 71.4) be assigned to packages for criticality
control.  Further, the fissile material exemptions and general license
provisions allow any licensee to make shipments without first seeking NRC

A fairly realistic computer model of the enriched uranium-beryllium oxide
waste packages, as loaded for shipment into a sea-land container, and at 0.5
grams per liter, could not be demonstrated to provide adequate nuclear
criticality safety.  Because the current regulations would allow the
possibility of criticality in fissile exempt shipments, and since there is no
assurance that such shipments will not occur, NRC intends to revise 10
CFR Part 71 to address exclusion of beryllium and other special moderating
material (e.g., deuterium and graphite) in the shipment of fissile materials,
and to limit the amount of fissile exempt material that can be transported in
a single consignment.

NRC has contacted the U.S. Department of Energy (DOE) and the DOT on this
issue.  DOE is a shipper of fissile material, which could include the special
moderating materials in question.  NRC and DOT are coordinating the revisions
to their respective regulations.

NRC notes that very few licensees are involved in the shipment of fissile
materials with beryllium, graphite, or deuterium.  However, for those
licensees that are involved in such shipments, it is important that programs
be assessed to ensure that adequate criticality safety is provided where
fissile materials are transported with materials known or expected to have
moderating properties greater than water.  As demonstrated by the licensee in
this case, the existing fissile material exemptions cannot be presumed,
without independent analysis, to preclude nuclear criticality in all cases.

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This information notice requires no specific action nor written response.  If
you have any questions about the information in this notice, please contact
the individual listed below, or the appropriate NRC regional office.

                                Charles J. Haughney, Acting Director
                                Spent Fuel Project Office
                                Office of Nuclear Material Safety
                                  and Safeguards

Technical contact:  Earl P. Easton, NMSS
                    (301) 415-8520

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