[Federal Register Volume 66, Number 50 (Wednesday, March 14, 2001)]
[Notices]
[Pages 14939-14940]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-6304]


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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 Facility Operating License No. DPR-69, which 
authorizes operation of Calvert Cliffs Nuclear Power Plant, Unit 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, in part, to the generation of hydrogen gas from a metal-water 
reaction between the reactor coolant and reactor fuel having 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 enable CCNPP2 to operate in 
Cycle 14 with a core containing a lead fuel (test) assembly (LFA) 
including fuel rods with advanced zirconium alloy cladding.

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 Sec. 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

[[Page 14940]]

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 a calculation demonstrating adequate ECCS 
performance for CCNPP2 and has shown that use of the lead fuel assembly 
does not have a significant impact on that previous calculation. The 
lead fuel assembly, with the zirconium-based alloy cladding, meets the 
same design basis as the Zircaloy-4 fuel which is currently in the 
CCNPP2 reactor core and has similar thermal-hydraulic characteristics. 
Because the LFA will be placed in a non-limiting location (Technical 
Specification 4.2.1 limits placement of the LFA to a non-limiting 
location in the core), the placement scheme and the similarity of the 
advanced alloys to Zircaloy-4 will assure that the behavior of the fuel 
rods clad with these alloys are bounded by the fuel performance and 
safety analyses performed for the Zircaloy-4 clad rods currently in the 
Unit 2 core. No safety limits will be changed or setpoints altered as a 
result of using the lead fuel assembly.
    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 LFA and fuel currently in use at 
CCNPP2 are of like geometry. Therefore, the staff concludes that use of 
the LFA will not introduce a mixed core penalty into the safety 
analyses for CCNPP2.
    Based on the above, the staff finds that the licensee has achieved 
the underlying purpose of 10 CFR 50.46 and 10 CFR part 50, appendix K 
with respect to use of the LFA at CCNPP2.
    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 small number of fuel rods in the lead 
fuel assembly containing advanced zirconium-based claddings in 
conjunction with the chemical similarity of the advanced claddings to 
zircaloy and ZIRLO ensures that previous calculations of hydrogen 
production resulting from a metal-water reaction would not be 
significantly changed. The licensee calculated the metal-water reaction 
rate for the advanced zirconium-based cladding material and determined 
that the amount of hydrogen generated will be within the design basis. 
As such, the licensee has achieved the underlying purpose of 10 CFR 
50.44.
    The staff examined the licensee's rationale to support the 
exemption request and concurred that the use of an LFA in the Unit 2 
core for Cycle 14 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 would not serve the underlying 
purpose of the rule.
    Therefore, the staff concludes that granting an exemption under the 
special circumstances of 10 CFR 50.12(a)(2)(ii) is appropriate and that 
an LFA containing fuel rods with advanced zirconium alloy cladding may 
be used in CCNPP Unit 2, Cycle 14.

4.0  Conclusion

    Accordingly, 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, Secs. 50.44, 50.46, and 10 CFR part 50, appendix K, 
for CCNPP2.
    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 (66 FR 11608).

    This exemption is effective upon issuance.
    Dated at Rockville, Maryland, this 6th day of March 2001.
    For the Nuclear Regulatory Commission.
John A. Zwolinski,
Director, Division of Licensing Project Management, Office of Nuclear 
Reactor Regulation.
[FR Doc. 01-6304 Filed 3-13-01; 8:45 am]
BILLING CODE 7590-01-P