[Federal Register Volume 64, Number 43 (Friday, March 5, 1999)]
[Notices]
[Pages 10728-10729]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-5474]


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NUCLEAR REGULATORY COMMISSION

[Docket Nos. STN 50-454 and STN 50-455]


Commonwealth Edison Company (Byron Station, Units 1 and 2); 
Exemption

I

    The Commonwealth Edison Company (ComEd, the licensee) is the holder 
of Facility Operating License Nos. NPF-37 and NPF-66, which authorize 
operation of Byron Station, Units 1 and 2. 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.
    The facility consists of two pressurized-water reactors at the 
licensee's site in Ogle County, Illinois.

II

    Section 50.44 of Title 10 of the Code of Federal Regulations, 
``Standards 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 this 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 
this section. ECCS cooling performance must be calculated in accordance 
with an acceptable evaluation model and must be calculated for a number 
of postulated

[[Page 10729]]

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 a Lead Test Assembly 
(LTA) with a tin composition that is less than the licensing basis for 
ZIRLO tin composition, as defined in Westinghouse design 
specifications.
    Section 50.12 of Title 10 of the Code of Federal Regulations, 
``Specific Exemptions,'' states, among other items, 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 licensee provided testing and evaluations which demonstrated 
that the intent of the regulations continue to be met since all aspects 
of safety, including mechanical, neutronic, thermal hydraulic, 
transient, and LOCA analyses results fall within those approved for the 
current 17x17 VANTAGE + fuel assemblies Analysis of Record for Byron 
Station, Units 1 and 2. The staff has reviewed the licensee's analysis 
and concluded in a Safety Evaluation dated February 26, 1999, that the 
licensee has demonstrated prudent judgment in the use of LTAs, and the 
licensee's analyses remain bounding for the LTAs. Therefore, 
application of the regulation in the particular circumstances is not 
necessary to achieve the underlying purpose of the rule.

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 the Commonwealth 
Edison Company 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 (64 FR 9549).
    This exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 26th day of February, 1999.

    For the Nuclear Regulatory Commission.
Roy P. Zimmerman,
Acting Director, Office of Nuclear Reactor Regulation.
[FR Doc. 99-5474 Filed 3-4-99; 8:45 am]
BILLING CODE 7590-01-P