[Federal Register Volume 62, Number 215 (Thursday, November 6, 1997)]
[Notices]
[Pages 60109-60111]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-29343]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-416]


Exemption

    In the matter of Entergy Operations, Inc., System Energy 
Resources, Inc., South Mississippi Electric Power Association, 
Entergy Mississippi, Inc.; (Grand Gulf Nuclear Station, Unit 1)

I

    Entergy Operations, Inc. (the licensee) is the holder of Facility 
Operating License No. NPF-29, which authorizes operation of Grand Gulf 
Nuclear Station, Unit 1 (GGNS). The operating license provides, among 
other things, that the licensee is subject to all rules, regulations, 
and orders of the Nuclear Regulatory Commission (NRC or the Commission) 
now and hereafter in effect.
    The facility is a General Electric boiling water reactor at the 
licensee's site in Claiborne County, Mississippi.

II

    Title 10 CFR 70.24, ``Criticality Accident Requirements,'' 
paragraph (a) states, in part, that ``Each licensee authorized to 
possess special nuclear material [SNM] in a quantity exceeding 700 
grams of contained uranium-235, 520 grams of contained uranium-233, 450 
grams of plutonium, 1,500 grams of contained uranium-235 if no uranium 
enriched to more than 4 percent by weight of uranium-235 is present, 
450 grams of any combination thereof, or one-half such quantities if 
massive moderators or reflectors made of graphite, heavy water or 
beryllium may be present, shall maintain in each area in which such 
licensed special nuclear material is handled, used, or stored, a 
monitoring system meeting the requirements of [10 CFR 70.24](a)(1) or 
(a)(2), as appropriate, and using gamma-or neutron-sensitive radiation 
detectors which will energize clearly audible alarm signals if 
accidental criticality occurs. This section is not intended to require 
underwater monitoring when special nuclear material is handled or 
stored beneath water shielding or to require monitoring systems when 
special nuclear material is being transported when packaged in 
accordance with the requirements of Part 71 [(i.e., 10 CFR Part 71, 
``Packaging and Transportation of Radioactive Material,'')] of this 
chapter.''
    The licensee meets the quantity criteria in 10 CFR 70.24(a) and is, 
therefore, required to have a criticality accident monitoring system in 
each area in which SNM in any form is handled, used, or stored. The 
licensee has proposed an exemption to this requirement for the storage 
of two forms of SNM at the site: (1) not-in-use in-core nuclear 
instrumentation (e.g., source range monitors) and (2) onsite 
unirradiated fuel. For the unirradiated fuel, the exemption is 
requested for the following cases:
     The interval when the fuel, packaged for shipment to the 
site in accordance with 10 CFR Part 71, is taken from the shipping 
truck to the plant area where the Part 71 packaging is removed.
     The storage of the unirradiated fuel in the new fuel vault 
(NFV), instead of the spent fuel pool, after the packaging is removed.
    The very small quantity of SNM present in the nuclear 
instrumentation is in the form of thin coatings within the 
instrumentation and the unirradiated fuel assemblies would only be 
removed from the NRC-approved packaging in areas where criticality 
monitors are in use, and stored in either the NFV or the

[[Page 60110]]

spent fuel pool. The unirradiated fuel that is stored in the spent fuel 
pool would be monitored in accordance with 10 CFR 70.24(a), whereas 
there is not a criticality accident monitor in the NFV.
    An exemption from 10 CFR 70.24(a) is required for the licensee to 
store SNM at the site and not have a criticality accident monitoring 
system for the storage areas.

III

    Pursuant to 10 CFR 70.14, ``Specific exemptions,'' the Commission 
may, upon application of any interested person or upon its own 
initiative, grant such exemptions from the requirements of the 
regulations in this part as it determines are authorized by law and 
will not endanger life or property or the common defense and security, 
and are otherwise in the public interest.
    Pursuant to 10 CFR 70.24(d), any licensee who believes that good 
cause exists why it should be granted an exemption in whole or in part 
from the requirements of this section may apply to the Commission for 
such an exemption. Such application shall specify the reason for the 
relief requested.
    By letter dated July 15, 1996, as supplemented by letters dated 
March 7 and April 29, 1997, the licensee requested an exemption from 
the monitoring requirements of 10 CFR 70.24(a) for the storage of these 
two forms of SNM at the site. In those letters, the licensee provided 
the justification and reasons for requesting the exemption. The 
licensee did not request an exemption to the performance requirements 
of a criticality accident monitoring system that are specified in 10 
CFR 70.24(a)(1) or (a)(2).
    A previous exemption from the provisions of 10 CFR 70.24 for the 
storage of SNM was granted for GGNS in the July 15, 1981, SNM License 
No. 1882. This exemption expired with the SNM license when the 
operating license was issued for GGNS because the exemption was not 
reissued at that time. Therefore, the licensee has requested an 
exemption from the criticality accident monitoring requirements of 10 
CFR 70.24(a) specifically for the areas containing in-core 
instrumentation detectors (which are not in use) and unirradiated 
(fresh) fuel. For unirradiated fuel, the exemption is requested for the 
unirradiated fuel that is in NRC-approved packaging while the fuel is 
taken from the shipping trucks to the spent fuel pool area to be 
removed from the packaging, and for the unirradiated fuel that is 
stored in the NFV, instead of the spent fuel pool.
    The principal form of SNM at GGNS is in the form of nuclear fuel. 
Other quantities of SNM are also used or stored at the facility in the 
form of fissile material incorporated into in-core nuclear 
instrumentation (e.g., source range monitors, intermediate range 
monitors, local power range monitors, and traversing in-core probes). 
The instrumentation is being stored at the site within the security 
fence in different plant areas.
    The SNM in the nuclear instrumentation is in small quantities in 
thin coatings applied to the inside of sealed fission chambers 
contained within the instruments. The licensee has stated that the 
total amount of SNM contained in the nuclear instruments meets the 
``forms not sufficient to form a critical mass'' in Section 1.1 of 
Regulatory Guide 10.3, ``Guide for the Preparation of Applications for 
Special Nuclear Material Licenses of Less Than Critical Mass 
Quantities,'' Revision 1, dated April 1977. Thus, the licensee has 
committed that the total amount of SNM contained within in-core nuclear 
instrumentation will be less than a critical mass. Therefore, the small 
quantity of SNM in the nuclear instrumentation precludes inadvertent 
criticality.
    Unirradiated nuclear fuel is received at the site only in NRC-
approved Part 71 packaging. The entire Part 71 packaging consists of 
two right rectangular boxes consisting of an outer wooden container 
surrounding a inner metal container housing the unirradiated fuel. 
There is only cushioning material between the two boxes. The containers 
are designed in accordance with a certificate of compliance for 
radioactive materials packages issued by the NRC, in this case for the 
shipment of unirradiated fuel assemblies. It is the inner metal 
container that ensures that a geometrically safe configuration of the 
fuel is maintained during transport, handling, storage, and accident 
conditions, and that the introduction of any moderating agents to the 
fuel is precluded due to its leak-tight construction. Criticality is 
precluded due to the construction of the package and the storage 
configuration of the fuel in the package. This is based on a 
criticality analysis of the Part 71 packaging which limits the number 
of such packages on a shipping truck.
    The handling of unirradiated fuel at the site is governed by 
administrative and departmental procedures that specify New Fuel 
Processing and Criticality Rules to ensure that fuel is not 
inadvertently removed from the inner metal container until it is 
positioned in the fuel inspection area near the spent fuel pool of the 
auxiliary building where a criticality accident monitoring system 
meeting 70.24(a) is present. It is the metal container that is referred 
to when the licensee stated that the unirradiated fuel will only be 
removed from the NRC-approved packaging in the presence of a 
criticality accident monitoring system meeting 70.24(a).
    The unirradiated fuel is brought onsite on shipping trucks. The 
wooden containers are removed from the inner metal containers, and the 
unirradiated fuel is lifted in the metal container to the 208-foot 
level of the auxiliary building, and adjacent to the cask washdown pit 
and NFV of the spent fuel pool area. Only one metal container is lifted 
at a time, and the crane and lifting equipment used for the lift are 
certified. The plant areas that the metal containers would be moved 
through were inspected during a visit to the site and it was determined 
that the areas have drains to prevent the possibility of submerging the 
metal containers under water and creating a possible criticality 
condition. The only practical plant area where the new fuel could be 
submerged in water to introduce moderation is the spent fuel pool and 
there are 70.24(a) monitors in that area.
    In the spent fuel pool area, the fuel is removed from the 
containers, inspected and channeled, and then placed either in the 
spent fuel pool or the NFV. Currently the unirradiated fuel is placed 
only in the spent fuel pool and, while the fuel is in the spent fuel 
pool, it is monitored by a 70.24(a) monitoring system; however 
unirradiated fuel may be stored inside the NFV and there is not a 
criticality accident monitor in the NFV. The design basis criticality 
margin requirements for the NFV is to maintain the unirradiated fuel in 
the vault at a subcriticality margin of at least 0.05 (i.e., a k 
effective no more than 0.95). The new fuel would be stored in racks 
that are designed to withstand all credible static and dynamic loadings 
to prevent damage and distortion of the racks, and to maintain the 
design subcriticality margin of 0.05 whether the vault is dry or 
flooded with unborated water, because unborated water would moderate 
the fuel and reduce the subcriticality margin. The racks are 
constructed in accordance with the quality assurance requirements of 
Appendix B to 10 CFR Part 50 and are categorized as Safety Class 2 and 
Seismic Category I. The vault is in a concrete, Seismic Category I 
building that is designed to Regulatory Guides 1.13 and 1.29 which 
precludes the deleterious effects on the fuel in the NFV by natural 
phenomena such as

[[Page 60111]]

earthquakes, tornados, hurricanes, tornado missiles, and floods. To 
prevent water moderation, there is a drain at the low point of the 
vault to remove water in the vault to prevent accumulation of water 
within the NFV and no fuel is placed in the vault if there is water in 
the vault. The licensee also has procedures to prevent the introduction 
of an optimum moderation inside the vault (e.g., using pressurized 
water fire extinguishers instead of foam for combating fires around 
fuel) which could decrease the subcriticality margin to a value greater 
than the design value of 0.05. Although the Technical Specifications 
for Grand Gulf do not specifically limit the enrichment of the fuel 
onsite including the NFV, the k-effective for spent fuel or new fuel in 
the fuel racks and submerged in water is limited to 0.95 by the 
Technical Specifications and the enrichment of the fuel onsite is 
limited because the k-effective for the NFV is not allowed to be 
greater than 0.95. The fuel enrichment is a contributor to the value of 
k-effective. Therefore, the design of the NFV will preclude inadvertent 
criticality of the new fuel in the vault.
    Therefore, based on the licensee's letters and the staff's 
evaluation, the Commission concludes that good cause exists for 
granting an exemption to the criticality monitoring requirements of 10 
CFR 70.24(a) in storage areas for (1) in-core instrumentation detectors 
which are not in use and (2) unirradiated fuel stored in the NFV. Based 
on the information provided by the licensee, there is reasonable 
assurance that the nuclear instrumentation and unirradiated fuel will 
remain subcritical during handling and storage in areas where 
critically accident monitors required by 10 CFR 70.24(a) are not 
present. Additionally, all fuel storage and handling areas will 
continue to be monitored to detect conditions that may result in 
excessive radiation levels as required by General Design Criterion 63.

IV

    For the foregoing reasons, pursuant to 10 CFR 70.24(d), the NRC 
staff has determined that good cause has been shown for granting an 
exemption to the criticality monitoring requirements of 10 CFR 
70.24(a).
    Accordingly, the Commission has determined that, pursuant to 10 CFR 
70.14, an exemption is authorized by law, will not endanger life or 
property or common defense and security, and is otherwise in the public 
interest. Therefore, with the total amount of SNM contained in the in-
core nuclear instruments less than a critical mass, as defined by 
Section 1.1 of Regulatory Guide 10.3 (Revision 1, dated April 1977), 
with the unirradiated fuel assemblies only removed from the NRC-
approved metal containers in areas where criticality monitors are 
present, and with administrative controls to prevent optimum moderation 
of the unirradiated fuel in the NFV, the Commission hereby grants 
Entergy Operations, Inc. an exemption from the criticality monitoring 
requirements of 10 CFR 70.24(a) for the storage of not-in-use in-core 
nuclear instrumentation and of unirradiated fuel in the NFV.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will have no significant impact on the 
quality of the human environment (62 FR 55837). This exemption is 
effective upon issuance.

    Dated at Rockville, Maryland, this 31st day of October 1997.

    For the Nuclear Regulatory Commission.
Samuel J. Collins,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 97-29343 Filed 11-5-97; 8:45 am]
BILLING CODE 7590-01-P