[Federal Register Volume 62, Number 189 (Tuesday, September 30, 1997)]
[Notices]
[Page 51167]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-25900]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-338]
In the Matter of Virginia Electric and Power Company North Anna
Power Station, Unit Nos. 1 and 2; Exemption and 50-339
I
The Virginia Electric and Power Company (the licensee) is the
holder of Facility Operating License Nos. NPF-4 and NPF-7, which
authorize operation of the North Anna Power Station (NAPS), Unit Nos. 1
and 2. The licenses provide, among other things, that the licensee be
subject to all rules, regulations, and Orders of the Nuclear Regulatory
Commission (the Commission) now or hereafter in effect.
The facility consists of two pressurized-water reactors at the
licensee's site located in Louisa County, Virginia.
II
The Code of Federal Regulations at 10 CFR 70.24, ``Criticality
Accident Requirements,'' requires that each licensee authorized to
possess special nuclear material (SNM) shall maintain a criticality
accident monitoring system in each area where such material is handled,
used, or stored. Subsections (a)(1) and (a)(2) of 10 CFR 70.24 specify
detection, sensitivity and coverage capabilities of the monitors
required by 10 CFR 70.24(a). Subsection (a)(3) requires licensees to
maintain emergency procedures for each area in which this licensed SNM
is handled, used, or stored.
Subsection (d) of 10 CFR 70.24 states that any licensee who
believes that there is good cause why it should be granted an exemption
from all or part of 10 CFR 70.24 may apply to the Commission for such
an exemption and shall specify the reasons for the relief requested.
III
By letter dated January 28, 1997, as supplemented March 24, 1997,
Virginia Electric and Power Company requested an exemption from 10 CFR
70.24(a). The Commission technical staff has reviewed the licensee's
submittal and has determined that inadvertent criticality is not likely
to occur in SNM handling or storage areas at NAPS, Units 1 and 2.
At North Anna, SNM is present principally as nuclear fuel. Other
small quantities of SNM are used on site. However, the total amount
used in non-fuel applications is significantly less than the quantity
specified in 10 CFR 70.24(a). The small quantity of non-fuel SNM
present, and the form in which it is stored and used, precludes an
inadvertent criticality. Therefore, SNM used as nuclear fuel is the
only material on site subject to the requirements of 10 CFR 70.24(a).
Nuclear fuel is stored in the new fuel storage area and the spent
fuel pool. New fuel is stored dry (in air) in the new fuel storage
area. The spent fuel pool is used to store irradiated fuel under water
after its discharge from the reactor, and new fuel prior to loading
into the reactor.
The new fuel storage area is used to receive and store new fuel in
a dry condition upon arrival on site and prior to loading in the
reactor or spent fuel pool. The spacing between new fuel assemblies in
the storage racks is sufficient to maintain the array in a subcritical
condition even under accident conditions assuming the presence of
moderator. The maximum nominal enrichment of 4.3 wt% U-235 for the new
fuel assemblies results in a maximum keff of less than 0.95
under conditions of accidental flooding by unborated water and
keff less than 0.98 under conditions of low-density optimum
moderation. The staff has found the design of the licensee's new fuel
storage racks to be adequate to store fuel enriched to 4.3 wt% U-235.
Consistent with Technical Specification Section 5.6.1.1, the spent
fuel pool is designed to store the fuel in a geometric array that
precludes criticality. The spent fuel racks are designed such that the
effective neutron multiplication factor, keff, will remain
less than or equal to 0.95 under all normal and accident conditions for
fuel of maximum nominal enrichment of 4.3 wt% U-235.
Nuclear fuel is moved between the shipping container, the new fuel
storage racks, the reactor vessel, and the spent fuel pool to
accommodate refueling operations. In all cases, fuel movements are
procedurally controlled and designed to preclude conditions involving
criticality concerns.
The purpose of the criticality monitors required by 10 CFR 70.24 is
to ensure that if a criticality were to occur during the handling of
nuclear material, personnel would be alerted to that fact and would
take appropriate action. Although the staff has determined that such an
accident is not likely to occur, the licensee has radiation monitors,
as required by General Design Criterion 63, in fuel storage and
handling areas. These monitors have associated area alarms and control
room annunciators and would detect excessive radiation levels and will
alert personnel to allow them to initiate appropriate emergency
procedures and safety actions. The low probability of an inadvertent
criticality together with the licensee's adherence to General Design
Criterion 63 constitute good cause for granting an exemption to the
requirements of 10 CFR 70.24(a).
IV
The Commission has determined that, pursuant to 10 CFR 70.14, this
exemption is authorized by law, will not endanger life or property or
the common defense and security, and is otherwise in the public
interest; therefore, the Commission hereby grants Virginia Electric and
Power Company the exemption from the requirements of 10 CFR 70.24(a)
for North Anna Power Station, Unit Nos. 1 and 2, relating to
criticality accident monitoring requirements.
V
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will not result in any significant adverse
environmental impact (62 FR 49540).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 23rd day of September 1997.
For The Nuclear Regulatory Commission.
Frank J. Miraglia,
Acting Director, Office of Nuclear Reactor Regulation.
[FR Doc. 97-25900 Filed 9-29-97; 8:45 am]
BILLING CODE 7590-01-P
