[Federal Register Volume 62, Number 144 (Monday, July 28, 1997)]
[Notices]
[Pages 40388-40389]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-19802]



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NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-317 and 50-318]


Baltimore Gas and Electric Company; Calvert Cliffs Nuclear Power 
Plant, (Unit Nos. 1 and 2)

Exemption

I

    The Baltimore Gas and Electric Company (BGE) is the holder of 
Facility Operating License Nos. DPR-53 and DPR-69 for the Calvert 
Cliffs Nuclear Power Plant, Unit Nos. 1 and 2 (Calvert Cliffs). The 
licenses provide, among other things, that the licensee is subject to 
all rules, regulations, and orders of the Commission now or hereafter 
in effect.

II

    Subsection (a) of 10 CFR 70.24, ``Criticality Accident 
Requirements,'' requires that each licensee authorized to possess 
special nuclear material shall maintain in each area where such 
material is handled, used, or stored, an appropriate criticality 
monitoring system. In accordance with Subsection (a)(1) of 10 CFR 
70.24, coverage of all such areas at Calvert Cliffs shall be provided 
by two criticality detectors. However, exemptions may be requested 
pursuant to 10 CFR 70.24(d), provided that the licensee believes that 
good cause exists for the exemption.
    By letter dated August 19, 1996, as supplemented February 14, 1997, 
the licensee requested an exemption from the requirements of 10 CFR 
70.24(a). A previous exemption from the provisions of 10 CFR 70.24 for 
the storage of special nuclear material, including reactor fuel 
assemblies [maximum amount of 2,440 kg of U-235 in uranium enriched to 
no more than 3.00 weight percent (w/o)] for Unit 1 and maximum amount 
of 2450 Kg of U-235 in uranium enriched to no more than 3.05% was 
granted to Baltimore Gas and Electric Company for Calvert Cliffs Unit 1 
in NRC Materials License No. SNM-1364 and for Calvert Cliffs Unit 2 in 
NRC Materials License No. SNM-1624. The materials licenses were issued 
on August 23, 1973, for Unit 1 and May 18, 1976, for Unit 2.
    The materials licenses expired upon conversion of the construction 
permits to operating licenses, which was July 31, 1974, for Unit 1 and 
November 30, 1976, for Unit 2, respectively. The basis for the current 
exemption request is the same as for the original request. The licensee 
proposes to handle and store unirradiated fuel without having a 
criticality monitoring system as required by 10 CFR 70.24.
    The basis for the exemption is that inadvertent or accidental 
criticality will be precluded, in accordance with General Design 
Critrion 62 through compliance with the Calvert Cliffs Technical 
Specifications, the geometric spacing of fuel assemblies in the new 
fuel storage racks and spent fuel storage pool, and administrative 
controls imposed on fuel handling procedures.
    Special nuclear material, as nuclear fuel, is stored in the spent 
fuel pool, the new fuel storage racks, and the Independent Spent Fuel 
Storage Installation. 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 Independent Spent Fuel Storage 
Installation utilizes dry canisters to store spent fuel.
    Special nuclear material is also present in the form of excore 
fission chamber detectors and startup neutron sources. The small 
quantity of special nuclear material present in these latter items 
precludes an inadvertent criticality.
    The spent fuel pool is designed to store the fuel in a geometric 
array using a solid neutron absorber that precludes criticality. The 
effective neutron multiplication factor, K<INF>eff</INF>, is maintained 
less than or equal to 0.95 by the solid neutron absorber. Although 
soluble boron is maintained in the spent fuel pool, no credit is taken 
for it in determining K<INF>eff</INF>.
    The new fuel storage racks may be 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 enrichment of 5.0 wt% U-235 for the 
new fuel assemblies results in a maximum K<INF>eff</INF> of 0.89 at a 
water density of 1.0 gm/cc (fully flooded), and a K<INF>eff</INF> of 
less than 0.89 for aqueous foam at optimum moderation conditions.
    Nuclear fuel is moved between the new fuel storage racks, the 
reactor vessel, the refueling pool, and the spent fuel pool to 
accommodate refueling operations. In addition, fuel is moved into the 
facility and within the reactor vessel, or within the spent fuel pool. 
In all cases, fuel movements are procedurally controlled and designed 
to preclude conditions involving criticality concerns. These procedural 
controls include:
    1. Plastic bags or other dust covers placed around new core 
components are removed or rendered incapable of holding water prior to 
inserting the assemblies into the new fuel storage racks.
    2. Only the auxiliary hook of the spent fuel cask handling crane 
may be used to move new fuel. Therefore, only one fuel assembly can be 
moved at a time.
    3. A maximum of two fuel assemblies are permitted outside of the 
approved shipping container or new fuel storage rack location at one 
time, one of which must be located in the new fuel inspection platform. 
Although two highly enriched assemblies may achieve criticality under 
close proximity, fully flooded conditions, it is highly improbable that 
the required water level for neutron moderation could be attained. The 
spent fuel pool area and new fuel handling areas would have to be 
flooded to an elevation approximately 17 feet above the floor. Based on 
the possible sources of water, achieving this fully flooded condition 
would require blockage of floor drains, sealing of access doors, and 
numerous procedure violations. In addition, the spent fuel pool high 
level alarm would alert operators of flooding from any of these 
sources. Since no fire protection sprinkler system exists in the new 
fuel handling area, there is no source of low-density aqueous foam 
moderation.
    Technical Specifications also preclude certain movements over the 
spent fuel pool to prevent an inadvertent criticality. Previous 
accident analyses have demonstrated that a fuel handling accident 
(i.e., a dropped fuel assembly) will not create conditions which could 
result in inadvertent criticality. Additionally, the Emergency Response 
Plan contains provisions for coping with unusual events such as a 
dropped fuel assembly.
    In order to meet the requirements of General Design Criterion 63, 
three area radiation monitors are provided for detecting high radiation 
levels in the spent fuel pool area, the spent fuel handling machine, 
and the new fuel storage area. At the alarm setpoint of these monitors, 
audible and visual alarms annunciate locally and in the control room. 
The output of each monitor is also recorded in the control room.
    Based upon the information provided, there is reasonable assurance 
that irradiated and unirradiated fuel will remain subcritical during 
handling and storage. The circumstances for granting an exemption to 10 
CFR 70.24 are met because criticality is precluded with the present 
design configuration, Technical

[[Page 40389]]

Specifications requirements, administrative controls, and the fuel 
handling equipment and procedures. Therefore, the staff has determined 
that the Licensee has demonstrated good cause for the granting of the 
exemption, thus the exemption should be granted.

III

    Accordingly, 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 Baltimore Gas 
and Electric Company an exemption as described in Section II above from 
10 CFR 70.24, ``Criticality Accident Requirements'' for Calvert Cliffs 
Nuclear Power Plant, Unit Nos. 1 and 2.
    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 (61 FR 52959).
    This exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 18th day of July 1997.

    For the Nuclear Regulatory Commission.
Samuel J. Collins,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 97-19802 Filed 7-25-97; 8:45 am]
BILLING CODE 7590-01-U