98-3582. In the Matter of Omaha Public Power District; Fort Calhoun Station, Unit No. 1; Exemption  

  • [Federal Register Volume 63, Number 29 (Thursday, February 12, 1998)]
    [Notices]
    [Pages 7186-7188]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 98-3582]
    
    
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    NUCLEAR REGULATORY COMMISSION
    
    [Docket No. 50-285]
    
    
    In the Matter of Omaha Public Power District; Fort Calhoun 
    Station, Unit No. 1; Exemption
    
    I
    
        The Omaha Public Power District (OPPD) is the holder of Facility 
    Operating License No. DPR-40 for the Fort Calhoun Station, Unit No. 1 
    (FCS) which authorizes operation of the Fort Calhoun Station, Unit No. 
    1. The license provides, among other things, that the licensee is 
    subject to all rules, regulations, and orders of the Commission now or 
    hereafter in effect.
        The facility consists of one pressurized-water reactor at the 
    licensee's site located in Washington County, Nebraska.
    
    II
    
        Section 70.24 of Title 10 of the Code of Federal Regulations, 
    ``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 and sensitivity requirements that these 
    monitors must meet. Subsection (a)(1) also specifies that all areas 
    subject to criticality accident monitoring must be covered by two 
    detectors. Subsection (a)(3) of 10 CFR 70.24 requires licensees to 
    maintain emergency procedures for each area in which this licensed SNM 
    is handled, used, or stored and provides that (1) the procedures ensure 
    that all personnel withdraw to an area of safety upon the sounding of a 
    criticality accident monitor alarm, (2) the procedures must include 
    drills to familiarize personnel with the evacuation plan, and (3) the 
    procedures designate responsible individuals for determining the cause 
    of the alarm and placement of radiation survey instruments in 
    accessible locations for use in such an emergency. Subsection (b)(1) of 
    10 CFR 70.24 requires licensees to have a means to identify quickly 
    personnel who have received a dose of 10 rads or more. Subsection 
    (b)(2) of 10
    
    [[Page 7187]]
    
    CFR 70.24 requires licensees to maintain personnel decontamination 
    facilities, to maintain arrangements for a physician and other medical 
    personnel qualified to handle radiation emergencies, and to maintain 
    arrangements for the transportation of contaminated individuals to 
    treatment facilities outside the site boundary. Paragraph (c) of 10 CFR 
    70.24 exempts Part 50 licensees from the requirements of paragraph (b) 
    of 10 CFR 70.24 for SNM used or to be used in the reactor. Paragraph 
    (d) of 10 CFR 70.24 states that any licensee who believes that there is 
    good cause why he 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
    
        The SNM that could be assembled into a critical mass at FCS is in 
    the form of nuclear fuel. In addition, the quantity of SNM other than 
    fuel that is stored on site in any given location is small enough to 
    preclude achieving a critical mass. As set forth below, the 
    Commission's technical staff has evaluated the possibility of an 
    inadvertent criticality of the nuclear fuel at FCS.
        By letter dated August 29, 1997, as supplemented by letter dated 
    October 23, 1997, the licensee requested an exemption from the 
    requirements of 10 CFR 70.24 in its entirety for FCS. The licensee 
    proposes to handle and store unirradiated fuel without having a 
    criticality monitoring system with the sensitivity required by 10 CFR 
    70.24.
        The basis for the staff to determine that inadvertent or accidental 
    criticality is extremely unlikely can be established through compliance 
    with the FCS 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.
        SNM, as nuclear fuel, is stored in the new fuel storage rack and in 
    the spent fuel pool. The spent fuel pool is used to store irradiated 
    fuel under water after its discharge from the reactor and new 
    (unirradiated) fuel prior to loading into the reactor. New fuel is 
    stored in the new fuel storage rack in a dry condition.
        SNM is also present in the form of excore fission chamber detectors 
    and startup neutron sources. The small quantity of SNM 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, keff, is maintained 
    less than or equal to 0.95 by the solid neutron absorber for fuel 
    enriched to 4.5 wt% U-235. Although soluble boron is maintained in the 
    spent fuel pool, no credit is taken for it in determining 
    keff.
        The new fuel storage racks may be used to receive and store new 
    fuel in a dry condition upon arrival onsite and prior to loading in the 
    reactor or spent fuel pool. The spacing between new fuel assemblies and 
    the solid neutron absorbers in the storage racks is sufficient to 
    maintain the dry array in a subcritical condition. The new fuel storage 
    rack is located at an elevation of 18.75 feet above the main floor 
    which provides adequate drainage and precludes flooding. Because no 
    fire protection sprinkler system exists in this area, there is no 
    source of low-density aqueous foam optimum moderation. The current 
    approved maximum enrichment of 4.5 wt% U-235 for the new fuel 
    assemblies results in a maximum keff of less than 0.90 under 
    dry conditions.
        Nuclear fuel is moved between the NRC-approved shipping containers, 
    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. For example, during new fuel receipt inspection, 
    FCS fuel handling procedures allow a maximum of two fuel assemblies to 
    be in the inspection stands in the receipt area (out of the shipping 
    container and not in the new fuel storage rack). However, when 
    installed in the inspection stands, both assemblies have an edge-to-
    edge separation distance in excess of 14 feet. This geometric spacing 
    is well in excess of that maintained by the NRC-approved shipping 
    container (approximately 3 inches). There are no sprinklers in the new 
    fuel receipt/storage room and the use of fire fighting equipment is 
    very unlikely since there are no combustible materials permanently 
    stored in this room. Even if fire suppression water were introduced 
    into the room, sufficient drainage exists to preclude potential 
    moderation of new fuel assemblies. Therefore, because of the large 
    physical separation of new fuel assemblies and the extremely unlikely 
    event of any potential moderation, there is sufficient assurance that 
    keff remains less than 0.95, thus precluding criticality.
        FCS was licensed to the 70 General Design Criteria for Nuclear 
    Power Plant Construction published as drafts in the Federal Register 
    (32 FR 10213) on July 11, 1967. Draft Criterion 18, Monitoring Fuel and 
    Waste Storage, was met. As noted in Section 11.2.3 and Appendix G of 
    the FCS Updated Safety Analysis Report, area monitoring of dose rates 
    is supplied in the containment and auxiliary buildings, including the 
    fuel storage areas. Local and control room alarms and indicators (not 
    necessarily meeting the 10 CFR 70.24 sensitivity requirements) are 
    provided to alert personnel to take appropriate action in the unlikely 
    event of excessive radiation levels due to accidental criticality.
        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 
    SNM, personnel would be alerted to that fact and would take appropriate 
    action. In view of the above information, the staff has determined that 
    it is extremely unlikely for an inadvertent criticality to occur in SNM 
    handling or storage areas at FCS. Criticality is precluded with the 
    present design configuration, Technical Specification requirements, 
    administrative controls, and the fuel handling equipment and 
    procedures. In addition, as described above, the licensee has radiation 
    monitors, as required by General Design Criterion 63, in fuel storage 
    and handling areas. These monitors will alert personnel to excessive 
    radiation levels and allow them to initiate appropriate safety actions. 
    The low probability of an inadvertent criticality, together with the 
    licensee's adherence to General Design Criterion 63, constitutes good 
    cause for granting an exemption to the requirements of 10 CFR 70.24.
    
    IV
    
        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 Omaha Public 
    Power District an exemption as described in Section II above from 10 
    CFR 70.24, ``Criticality Accident Requirements'' for the Fort Calhoun 
    Station.
        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 (63 FR 5821).
        This exemption is effective upon issuance.
    
    For the Nuclear Regulatory Commission.
    
    
    [[Page 7188]]
    
    
        Dated at Rockville, Maryland, this 6th day of February 1998.
    Frank J. Miraglia, Jr.,
    Acting Director, Office of Nuclear Reactor Regulation.
    [FR Doc. 98-3582 Filed 2-11-98; 8:45 am]
    BILLING CODE 7590-01-P
    
    
    

Document Information

Published:
02/12/1998
Department:
Nuclear Regulatory Commission
Entry Type:
Notice
Document Number:
98-3582
Pages:
7186-7188 (3 pages)
Docket Numbers:
Docket No. 50-285
PDF File:
98-3582.pdf