[Federal Register Volume 71, Number 37 (Friday, February 24, 2006)]
[Notices]
[Pages 9612-9613]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-2663]


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NUCLEAR REGULATORY COMMISSION


Notice of Availability of Documents Regarding Spent Fuel 
Transportation Package Response to the Caldecott Tunnel Fire Scenario

AGENCY: Nuclear Regulatory Commission.

ACTION: Notice of availability.

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FOR FURTHER INFORMATION CONTACT: Allen Hansen, Thermal Engineer, 
Criticality, Shielding and Heat Transfer Section, Spent Fuel Project 
Office, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear 
Regulatory Commission, Washington, DC 20005-0001. Telephone: (301) 415-
1390; fax number: (301) 415-8555; e-mail: [email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction

    Under contract with the Nuclear Regulatory Commission (NRC), The 
Pacific Northwest National Laboratory prepared a draft NUREG/CR report, 
``Spent Fuel Transportation Package Response to the Caldecott Tunnel 
Fire (CTF) Scenario.'' Highway tunnel fire accidents are very low 
frequency events, but can be severe, in terms of fire duration and peak 
temperatures. The CTF was chosen for the study because it represents a 
severe historical highway tunnel accident, even though it is a very low 
frequency event. This NUREG/CR documents the thermal analysis of one 
spent fuel transportation package, the NAC International Model No. LWT 
(``NAC LWT''), exposed to boundary conditions simulating the CTF 
scenario.
    The results of this study strongly indicate that no spent nuclear 
fuel (SNF) particles or fission products would be released from the NAC 
LWT or a similar spent fuel shipping cask involved in a severe tunnel 
fire such as the Caldecott highway tunnel fire. The peak internal 
temperatures predicted for the NAC LWT in the analysis of the CTF 
scenario were not high enough to result in rupture of the fuel 
cladding. Therefore, it would not be expected that any radioactive 
material (i.e, SNF particles or fission products) would be released 
from within the fuel rods.
    The maximum NAC LWT temperatures experienced in the regions of the 
lid, vent and drain ports exceeded the seals' rated service 
temperatures, making it theoretically possible for a small release to 
occur, due to CRUD that might spall off of the surfaces of the fuel 
rods. However, any release is expected to be very small due to a number 
of factors. These include: (1) The tight clearances maintained between 
the lid and cask body by the lid closure bolts; (2) the low pressure 
differential between the cask interior and the outside; (3) the 
tendency of the small clearances to plug; and (4) the tendency of CRUD 
particles to settle or plate out. The potential releases calculated in 
Chapter 8 of this report for the NAC LWT truck cask indicate that the 
release of CRUD from the cask, if any, would be very small--less than 
an A2 quantity.

II. Summary

    The purpose of this notice is to provide the public an opportunity 
to review and comment on the Draft NUREG/CR thermal analysis, the 
consequence analyses and the conclusions.

III. Further Information

    The document related to this action is available on-line at http://www.nrc.gov/reading-rm/doc-collections/nuregs/docs4comment.html. In 
addition, a copy of this document has been posted electronically at the 
NRC's Electronic Reading Room at http://www.nrc.gov/reading-rm/adams.html. From this site, you can access the NRC's Agencywide 
Document Access and Management System (ADAMS), which provides text and 
image files of NRC's public documents. The ADAMS accession number for 
the document related to this notice is ML060330028. If you do not have 
access to ADAMS or if there are problems in accessing the document 
located in ADAMS, contact the NRC Public Document Room (PDR) Reference 
staff at 1-800-397-4209, 301-415-4737, or by e-mail to [email protected].
    This document may also be viewed electronically on the public 
computers located at the NRC's PDR, O 1 F21, One White Flint North, 
11555 Rockville Pike, Rockville, MD 20852. The PDR reproduction 
contractor will copy documents for a fee. Comments and questions on the 
draft NUREG/CR can be entered on-line or directed to the

[[Page 9613]]

NRC contact listed above by May 30, 2006. Comments received after this 
date will be considered if it is practical to do so, but assurance of 
consideration cannot be given to comments received after this date.

    Dated at Rockville, Maryland this 17 day of February, 2006.

    For the Nuclear Regulatory Commission.
Larry Campbell,
Chief, Criticality, Shielding and Heat Transfer Section, Spent Fuel 
Project Office, Office of Nuclear Material Safety, and Safeguards.
[FR Doc. E6-2663 Filed 2-23-06; 8:45 am]
BILLING CODE 7590-01-P