[Federal Register Volume 68, Number 74 (Thursday, April 17, 2003)]
[Notices]
[Pages 19037-19038]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-9442]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-318]


Calvert Cliffs Nuclear Power Plant, Inc., Calvert Cliffs Nuclear 
Power Plant, Unit No. 2; Exemption

1.0 Background

    Calvert Cliffs Nuclear Power Plant, Inc. (CCNPPI or the licensee) 
is the holder of Renewed Facility Operating License No. DPR-69, which 
authorizes operation of Calvert Cliffs Nuclear Power Plant, Unit No. 2 
(CCNPP2). The license provides, among other things, that the facility 
is subject to all rules, regulations, and orders of the U.S. Nuclear 
Regulatory Commission (NRC, the Commission) now or hereafter in effect.
    The facility consists of a pressurized-water reactor located in 
Calvert County in Maryland.

2.0 Purpose

    Title 10 of the Code of Federal Regulations (10 CFR), part 50, 
section 50.46 and Appendix K identify requirements for calculating 
emergency core cooling system (ECCS) performance for reactors 
containing fuel with zircaloy or ZIRLO cladding, and 10 CFR 50.44 
relates to the control of hydrogen gas generated in part from a metal-
water reaction between the reactor coolant and reactor fuel having 
zircaloy or ZIRLO cladding.
    Since 10 CFR 50.44, 10 CFR 50.46, and Appendix K specifically 
relate to the use of zircaloy or ZIRLO cladding, the licensee has 
requested a temporary exemption to 10 CFR 50.44, 10 CFR 50.46, and 
Appendix K that would allow CCNPP2 to operate in Cycles 15 and 16 with 
a core containing up to eight lead fuel assemblies (LFAs) clad with an 
advanced zirconium-based alloy (up to four LFAs containing fuel rods 
clad with Framatome proprietary zirconium-based M5 alloy, and up to 
four LFAs containing fuel rods clad with Westinghouse proprietary 
advanced zirconium-based alloys).

3.0 Discussion

    Pursuant to 10 CFR 50.12, the Commission may, upon application by 
any interested person or upon its own initiative, grant exemptions from 
the requirements of 10 CFR part 50, when (1) the exemptions are 
authorized by law, will not present an undue risk to public health or 
safety, and are consistent with the common defense and security; and 
(2) when special circumstances are present. Under section 50.12(a)(2), 
special circumstances include, among other things, when application of 
the regulation in the particular circumstance would not serve, or is 
not necessary to achieve, the underlying purpose of the rule.
    The underlying purpose of 10 CFR 50.46 and 10 CFR part 50, Appendix 
K, is to establish requirements for the calculation of ECCS performance 
and acceptance criteria for that performance in order to assure that 
the ECCS functions to transfer heat from the reactor core following a 
loss-of-coolant-accident (LOCA) such that (1) fuel and clad damage that 
could interfere with continued effective core cooling is prevented, and 
(2) clad metal-water reaction is limited to negligible amounts. The 
licensee has performed assessments of plant transients and accidents, 
including LOCAs, using methodologies approved for application to the 
Calvert Cliffs plants. Though the methodologies may not have been 
approved for licensing-basis analyses for some of the LFAs, the 
licensee provided information that confirmed that the methodologies 
were adequate for assessing them.
    The licensee's analyses indicate that the LFAs will not affect the 
present design basis analyses for CCNPP2 during Cycles 15 and 16. The 
licensee attributed this finding in part to positioning of the LFAs in 
non-limiting locations. The licensee has clarified that it will place 
the LFAs in locations that represent the normal CCNPP2 operational fuel 
duty, including in ``hot,'' though non-limiting, locations. The 
licensee believes this will provide data representative of the fuel 
operation and burnup for two cycles.
    Because the LFAs will be placed in non-limiting locations 
(Technical Specification 4.2.1 limits placement of LFAs to non-limiting 
locations in the core), the placement scheme and the similarity of the 
advanced zirconium-based alloy cladding used in the LFAs to the 
Zircaloy-4 clad rods, which are currently in the reactor core, will 
assure that the behavior of the LFAs will be bounded by the fuel 
performance and safety analyses performed for the Zircaloy-4 clad rods. 
No safety limits will be changed or setpoints altered as a result of 
using the LFAs.
    In similar reviews of applications to use advanced fuel, the staff 
found that fuels with advanced cladding do not introduce a mixed core 
penalty in licensing safety analyses, provided that the resident fuel 
and the LFA were of like geometry. The licensee has indicated that the 
LFAs and fuel currently in use at CCNPP2 are of like geometry. 
Therefore, the staff concludes that use of the LFAs will not introduce 
a mixed core penalty into the safety analyses for CCNPP2.
    Based on the above, the staff finds that, with the LFAs in use, the 
ECCS performance calculations assure that the ECCS will function to 
achieve the goals stated in 10 CFR 50.46 and 10 CFR part 50, Appendix 
K. Accordingly, the staff finds that application of section 50.46 and 
Appendix K with respect to use of the LFAs with advanced zirconium-
based alloy cladding at CCNPP2 is not necessary to achieve the 
underlying purpose of these regulations.
    The underlying purpose of 10 CFR 50.44 is to ensure that means are 
provided for the control of hydrogen gas that may be generated 
following a postulated LOCA. The licensee submitted supporting 
documentation that shows that the use of the Baker-Just equation to 
determine the metal-water reaction rate is conservative for the 
Framatome M5TM cladding and the Westinghouse advanced 
zirconium alloy cladding. Therefore, the amount of hydrogen generated 
by metal-water reaction in these materials will be within the design 
basis. As such, the licensee has achieved the underlying purpose of 10 
CFR 50.44, and application of that rule with respect to use of the LFAs 
with advanced zirconium-based alloy cladding at CCNPP2 is not necessary 
to achieve that purpose.
    The staff examined the licensee's rationale to support the 
exemption request and, as set forth above, has determined that the use 
of LFAs with advanced zirconium-based alloy cladding in the Unit 2 core 
for Cycles 15 and 16 would meet the underlying purpose of 10 CFR 50.44, 
10 CFR 50.46, and 10 CFR part 50, Appendix K. Application of these 
regulations in these circumstances is not necessary to achieve the 
underlying purpose of the rule.

[[Page 19038]]

    Therefore, the staff concludes that granting an exemption under the 
special circumstances of 10 CFR 50.12(a)(2)(ii) is appropriate.

4.0 Conclusion

    For the reasons set forth above, the Commission has determined 
that, pursuant to 10 CFR 50.12(a), the exemption is authorized by law, 
will not endanger life or property or common defense and security, and 
is, otherwise, in the public interest. Also, special circumstances are 
present. Therefore, the Commission hereby grants CCNPPI an exemption 
from the requirements of 10 CFR part 50, section 50.44, section 50.46, 
and 10 CFR part 50, Appendix K, with respect to the use of LFAs with 
advanced zirconium-based alloy cladding at CCNPP2 during cycles 15 and 
16.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will not have a significant effect on the 
quality of the human environment (67 FR 77085 and 67 FR 75864).
    This exemption is effective upon issuance.

    Dated in Rockville, Maryland, this 11th day of April, 2003.

    For the Nuclear Regulatory Commission.
John A. Zwolinski,
Director, Division of Licensing Project Management, Office of Nuclear 
Reactor Regulation.
[FR Doc. 03-9442 Filed 4-16-03; 8:45 am]
BILLING CODE 7590-01-P