[Federal Register Volume 65, Number 57 (Thursday, March 23, 2000)]
[Notices]
[Pages 15656-15657]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-7241]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-346]


FirstEnergy Nuclear Operating Company (Davis-Besse Nuclear Power 
Station); Exemption

I

    The FirstEnergy Nuclear Operating Company (FENOC, the licensee) is 
the holder of Facility Operating License No. NPF-3, which authorizes 
operation of the Davis-Besse Nuclear Power Station (DBNPS). The license 
provides, among other things, that the license is subject to all rules, 
regulations, and orders of the Commission now or hereafter in effect.
    The facility consists of a pressurized-water reactor at the 
licensee's site in Ottawa County, Ohio.

II

    Section 50.44 of Title 10 of the Code of Federal Regulations, 
``Standard for Combustible Gas Control System in Light-Water-Cooled 
Power Reactors,'' requires, among other items, that each boiling or 
pressurized light-water nuclear power reactor fueled with oxide pellets 
within cylindrical zircaloy or ZIRLO cladding, must, as provided in 
paragraphs (b) through (d) of that section, include means for control 
of hydrogen gas that may be generated, following a postulated loss-of-
coolant accident (LOCA) by--(1) Metal-water reaction involving the fuel 
cladding and the reactor coolant, (2) Radiolytic decomposition of the 
reactor coolant, and (3) Corrosion of metals.
    Section 50.46 of Title 10 of the Code of Federal Regulations, 
``Acceptance Criteria for Emergency Core Cooling Systems for Light-
Water Nuclear Power Reactors,'' requires, among other items, that each 
boiling or pressurized light-water nuclear power reactor fueled with 
uranium oxide pellets within cylindrical zircaloy or ZIRLO cladding 
must be provided with an emergency core cooling system (ECCS) that must 
be designed so that its calculated cooling performance following 
postulated LOCAs conform to the criteria set forth in paragraph (b) of 
that section. ECCS cooling performance must be calculated in accordance 
with an acceptable evaluation model and must be calculated for a number 
of postulated LOCAs of different sizes, locations, and other properties 
sufficient to provide assurance that the most severe postulated LOCAs 
are calculated.
    Appendix K to Part 50 of Title 10 of the Code of Federal 
Regulations, ``ECCS Evaluation Models,'' requires, among other items, 
that the rate of energy release, hydrogen generation, and cladding 
oxidation from the metal/water reaction shall be calculated using the 
Baker-Just equation.
    10 CFR 50.44, 10 CFR 50.46, and 10 CFR part 50, Appendix K, make no 
provisions for use of fuel rods clad in a material other than Zircaloy 
or ZIRLO. The licensee has requested the use of Framatome Cogema Fuels 
(FCF) ``M5'' advanced alloy for fuel rod cladding for the DBNPS 
operating Cycle 13. The M5 alloy is a proprietary zirconium-based alloy 
comprised of primarily zirconium (99 percent) and niobium 
(1 percent). The elimination of tin has resulted in 
superior corrosion resistance and reduced irradiation induced growth 
relative to both standard Zircaloy (1.7% tin) and low-tin Zircaloy 
(1.2% tin). The addition of niobium increases ductility which is 
desirable to avoid brittle failures. Since the chemical composition of 
the M5 alloy differs from the specifications for Zircaloy or ZIRLO, a 
plant-specific exemption is required to allow the use of the M5 alloy 
as a cladding material at the DBNPS.
    Section 50.12 of Title 10 of the Code of Federal Regulations, 
``Specific Exemptions,'' states, among other items, that the Commission 
may, upon application by any interested person or upon its own 
initiative, grant exemptions from the requirements of the regulations 
of this part, which are authorized by law, will not present an undue 
risk to the public health and safety, and are consistent with the 
common defense and security. The Commission will not consider granting 
an exemption unless special circumstances are present. Special 
circumstances are present whenever application of the regulation in the 
particular circumstances would not serve the underlying purpose of the 
rule or is not necessary to achieve the underlying purpose of the rule.

III

    The underlying purpose of 10 CFR 50.46 is to ensure that facilities 
have adequate acceptance criteria for ECCS. In its topical report BAW-
10227P, ``Evaluation of Advanced Cladding and Structural Material (M5) 
in PWR Reactor Fuel,'' Framatome Cogema Fuels (FCF) demonstrated that 
the effectiveness of the ECCS will not be affected by a change from 
Zircaloy fuel rod cladding to M5 fuel rod cladding. Analysis described 
in the topical report also demonstrates that the ECCS acceptance 
criteria applied to reactors fueled with Zircaloy clad fuel are also 
applicable to reactors fueled with M5 fuel rod cladding.
    The underlying purposes of 10 CFR 50.44 and 10 CFR part 50, 
Appendix K, paragraph I.A.5, are to ensure that cladding oxidation and 
hydrogen generation are appropriately limited during a LOCA and 
conservatively accounted for in the ECCS evaluation model. 
Specifically, Appendix K requires that the Baker-Just equation be used 
in the ECCS evaluation model to determine the rate of energy release, 
cladding oxidation, and hydrogen generation. In their topical report, 
FCF demonstrated that the Baker-Just model is conservative in all post-
LOCA scenarios with respect to the use of the M5 advanced alloy as a 
fuel rod cladding material, and that the amount of hydrogen generated 
in an M5-clad core during a LOCA will remain within the DBNPS design 
basis.
    The staff has reviewed the FCF's advanced cladding and structural 
material, M5, for pressurized water reactor fuel mechanical designs as 
described in BAW-10227P. In a Safety Evaluation dated February 4, 2000, 
the staff concluded that, to the extent and limitations specified in 
the staff's evaluation, the M5 properties and mechanical design 
methodology are acceptable for referencing in fuel reload

[[Page 15657]]

licensing applications. Therefore, since the underlying purposes of 10 
CFR 50.44, 10 CFR 50.46, and 10 CFR part 50, Appendix K, paragraph 
I.A.5 are achieved through the use of the M5 advanced alloy as a fuel 
rod cladding material, the special circumstances required by 10 CFR 
50.12(a)(2)(ii) for the granting of exemptions to 10 CFR 50.44 and 10 
CFR part 50, Appendix K, paragraph I.A.5 exist.

IV

    The Commission has determined that, pursuant to 10 CFR 50.12, 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 FENOC an exemption 
from the requirements of 10 CFR 50.44, 10 CFR 50.46, and 10 CFR part 
50, Appendix K.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will have no significant impact on the 
environment (65 FR 794).
    This exemption is effective upon issuance.

    For the Nuclear Regulatory Commission.

    Dated at Rockville, Maryland, this 15th day of March 2000.
John A. Zwolinski,
Director, Division of Licensing Project Management, Office of Nuclear 
Reactor Regulation.
[FR Doc. 00-7241 Filed 3-22-00; 8:45 am]
BILLING CODE 7590-01-P