[Federal Register Volume 62, Number 47 (Tuesday, March 11, 1997)]
[Notices]
[Pages 11160-11161]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-5961]
=======================================================================
-----------------------------------------------------------------------
DEFENSE NUCLEAR FACILITIES SAFETY BOARD
[Recommendation 97-1]
Safe Storage of Uranium-233
AGENCY: Defense Nuclear Facilities Safety Board.
ACTION: Notice; recommendation.
-----------------------------------------------------------------------
SUMMARY: The Defense Nuclear Facilities Safety Board has made a
recommendation to the Secretary of Energy pursuant to 42 U.S.C. 2286a
concerning the Safe Storage of Uranium-233. The Board requests public
comments on this recommendation.
DATES: Comments, data, views, or arguments concerning this
recommendation are due on or before April 10, 1997.
ADDRESSES: Send comments, data, views, or arguments concerning this
recommendation to: Defense Nuclear Facilities Safety Board, 625 Indiana
Avenue, NW., Suite 700, Washington, DC 20004-2901.
FOR FURTHER INFORMATION CONTACT:
Kenneth M. Pusateri or Andrew L. Thibadeau at the address above or
telephone (202) 208-6400.
Dated: March 6, 1997.
John T. Conway,
Chairman.
[Recommendation 97-1] Safe Storage of Uranium-233
Dated: March 3, 1997.
Approximately one ton of Uranium-233 (233U), a man-made
isotope of uranium, was produced by the Department of Energy (DOE) and
its predecessor agencies. This material has been studied extensively,
and uses were found for it in DOE's defense-related applications and in
nuclear reactor programs supported both by DOE and commercial
companies. The 233U in this country is now all in the possession
of DOE. It is presently stored at several DOE sites, predominantly
within defense nuclear facilities under the purview of the Defense
Nuclear Facilities Safety Board (Board). Almost all of the 233U
has been determined by DOE to be excess to its needs, and with minor
exceptions it is regarded as legacy material. As will be apparent from
the following, however, any future
[[Page 11161]]
processing or disposal of the 233U will be accompanied by deep
problems which will cause handling of the relatively small inventory of
this material to be exceptionally difficult.
Most of this material in DOE storage has a specific alpha-activity
which approaches that of weapons grade plutonium. Furthermore, all
233U contains an amount of 232U which varies from one lot to
another. One of the daughter products in the radioactive decay chain of
the 232U is Thallium-208 (208Th). That isotope of Thallium
emits a high-energy (2.6 Mev) gamma ray when it decays. Depending on
the amount of 232U present in the 233U, the surrounding
radiation field can vary from somewhat less than one Rem/hr to several
tens of Rem/hr. This radiation field causes handling and processing of
any single item to be highly hazardous and very difficult to perform.
Even visual inspection of a container housing 233U will usually be
difficult.
DOE has recently completed a review of issues associated with
highly-enriched uranium. The results of that review have been made
available to the Board in a report entitled the Highly Enriched Uranium
Environmental, Safety and Health Vulnerability Assessment Report. This
report stated that 233U in storage exists in various forms
throughout the complex, including metal, compounds, and scrap material.
In addition, it noted that there was uncertainty as to the identity of
some of the items and the material condition of many of the storage
containers. Members of the Board's staff have also recently reviewed
the storage of 233U. The results of that review have been issued
by the Board as the report ``Uranium-233 Storage Safety at Department
of Energy Facilities'' (DNFSB/TECH-13). The assessments in that report
have led the Board to identify several areas of concern.
Responsibility for the 233U inventory remaining within the DOE
complex is diffuse. Several secretarial officers and office heads are
responsible for aspects of defense nuclear facilities that store
significant quantities of 233U. For example, Defense Programs is
responsible for Building 3019 at the Oak Ridge National Laboratory,
where more than 400 kg of 233U resides. Environmental Management
now has responsibility for the Chemical Processing Plant and the
Radioactive Waste Management Complex at the Idaho National Engineering
Laboratory, where there are about 350 kg of unirradiated 233U in
various chemical and physical forms and a large number of irradiated
nuclear fuel elements. An additional complication results from the role
of DOE's Office of Material Disposition in developing strategies for
final disposal of excess special nuclear material. By way of contrast
to this state of dispersed responsibility, the Board notes the better
practice of placing stabilization of plutonium residues under a single
project manager, in response to the Board's Recommendation 94-1.
Uncertainty as to the condition of many items of stored \233\U
generates additional concerns. Review of the original storage and
packaging of the items of \233\U reveals wide variations in practices.
Questions exist in some cases as to the original state and composition
of stored items. Furthermore, many of the containers in which U-233 is
stored have not been inspected for decades, and in some cases have not
even been accessed over this interval. The inactivity leads to
additional doubts as to the condition of the stored material, and
degrades even further the information base which should be improved
before it becomes necessary to process the contents of the containers
for ultimate disposal. It also raises questions as to how the storage
facilities themselves can be deactivated, cleaned up, and
decommissioned, since some will be contaminated with this highly
radioactive material.
It cannot be ruled out that problems exceeding those which
motivated the Board in issuance of its Recommendation 94-1 may be found
where \233\U is stored under conditions such that physical
deterioration can occur. For this reason it would appear prudent to
assess the adequacy of packaging of the items of \233\U as they are
presently stored, as well as the state of the storage facilities, and
to correct any problems that are found. The assessment would profit
from the example of DOE's implementation of the Board's Recommendation
94-1, in developing a standard for the interim packaging and storage of
plutonium. A similar standard would probably be appropriate for \233\U,
but some differences may be called for.
The Board understands that work is presently on-going within DOE to
address some of the above concerns. However, actions to deal with DOE's
remaining inventory of U-233 would be greatly enhanced by a more
systematic and focused approach. Therefore, the Board recommends that
DOE:
1. Establish a single line project to deal with issues attached to
safe storage of \233\U.
2. Develop standards to be used for packaging, transportation, and
interim and long-term storage of \233\U.
3. Characterize the items of \233\U presently in storage in DOE's
defense nuclear facilities, as to material, quantity, and type and
condition of storage container.
4. Evaluate the conditions and appropriateness of the vaults and
other storage systems used for the \233\U at DOE's defense nuclear
facilities.
5. Assess the state of storage of the items of \233\U in light of
the standards mentioned in recommendation 2 above.
6. Initiate a program to remedy any observed shortfalls in ability
to maintain the items of \233\U in acceptable interim storage.
7. Establish a plan for the measures that can eventually be used to
place the \233\U in safe, permanent storage.
8. Until these ultimate measures are taken, ensure that the DOE
complex retains the residue of technical knowledge and competence
needed to carry through all of the measures needed to ensure safe
storage of the \233\U in the short and the long term.
John T. Conway,
Chairman.
Appendix--Transmittal Letter to Acting Secretary of Energy
Defense Nuclear Facilities Safety Board
March 3, 1997.
The Honorable Charles B. Curtis,
Acting Secretary of Energy, 1000 Independence Avenue, SW,
Washington, DC 20585-1000
Dear Mr. Curtis: On March 3, 1997, the Defense Nuclear
Facilities Safety Board (Board), in accordance with 42 U.S.C.
Sec. 2286a(a)(5), unanimously approved Recommendation 97-1 which is
enclosed for your consideration. Recommendation 97-1 deals with the
Safe Storage of Uranium-233.
42 U.S.C. Sec. 2286d(a) requires the Board, after receipt by
you, to promptly make this recommendation available to the public in
the Department of Energy's regional public reading rooms. The Board
believes the recommendation contains no information which is
classified or otherwise restricted. To the extent this
recommendation does not include information restricted by the
Department of Energy under the Atomic Energy Act of 1954, 42 U.S.C.
Secs. 2161-68, as amended, please arrange to have this
recommendation promptly on file in your regional public reading
rooms.
The Board will publish this recommendation in the Federal
Register.
Sincerely,
John T. Conway
Chairman
Enclosure: c: Mr. Mark B. Whitaker, Jr.
[FR Doc. 97-5961 Filed 3-10-97; 8:45 am]
BILLING CODE 3670-01-M