[Federal Register Volume 75, Number 245 (Wednesday, December 22, 2010)]
[Notices]
[Pages 80546-80547]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-32144]


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NUCLEAR REGULATORY COMMISSION

[ Docket Nos. 50-280 and 50-281; NRC-2010-0283]


Virginia Electric and Power Company; Surry Power Station Unit 
Nos. 1 and 2; Exemption

1.0 Background

    Virginia Electric and Power Company (the licensee) is the holder of 
Facility Operating License Nos. DPR-32 and DPR-37 which authorizes 
operation of the Surry Power Station (SURRY) Unit Nos. 1 and 2. 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 
Surry County, Virginia.

2.0 Request/Action

    Pursuant to Title 10 of the Code of Federal Regulations (10 CFR), 
Section 50.12, ``Specific exemptions,'' the Virginia Electric and Power 
Company (VEPCO), by letter dated February 10, 2010,\1\ requested an 
exemption from certain requirements of 10 CFR 50.46, ``Acceptance 
criteria for emergency core cooling systems [ECCS] for light-water 
nuclear power reactors,'' and Appendix K to 10 CFR Part 50, ``ECCS 
Evaluation Models'' (Appendix K). The regulations in 10 CFR 50.46 
contain acceptance criteria for the ECCS for reactors fueled with 
zircaloy or ZIRLO<SUP>TM</SUP> cladding. In addition, Appendix K to 10 
CFR Part 50 requires that the Baker-Just equation be used to predict 
the rates of energy release, hydrogen concentration, and cladding 
oxidation from the metal/water reaction. The Baker-Just equation 
assumed the use of a zirconium alloy different than Optimized 
ZIRLO<SUP>TM</SUP>. The exemption request relates solely to the 
specific types of cladding material specified in these regulations. As 
written, the regulations presume the use of zircaloy or 
ZIRLO<SUP>TM</SUP> fuel rod cladding. Thus, an exemption from the 
requirements of 10 CFR 50.46 and Appendix K is needed to support the 
use of different fuel rod cladding material. Therefore, the licensee 
requested an exemption that would allow the use of Optimized 
ZIRLO<SUP>TM</SUP> fuel rod cladding at SURRY. The NRC staff will 
prepare a separate safety evaluation, fully addressing VEPCO's 
application for a related license amendment.
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    \1\ VEPCO letter to NRC, Agencywide Documents Access and 
Management System (ADAMS) Accession No. ML100470738.
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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 10 CFR 50.12(a)(2), 
special circumstances include, among other things, when application of 
the specific regulation in the particular circumstance would not serve, 
or is not necessary to achieve, the underlying purpose of the rule.

[[Page 80547]]

Authorized by Law

    This exemption would allow the use of Optimized ZIRLO<SUP>TM</SUP> 
fuel rod cladding material at SURRY. As stated above, 10 CFR 50.12 
allows the NRC to grant exemptions from the requirements of 10 CFR Part 
50. The NRC staff has determined that granting of the licensee's 
proposed exemption will not result in a violation of the Atomic Energy 
Act of 1954, as amended, or the Commission's regulations. Therefore, 
the exemption is authorized by law.

No Undue Risk to Public Health and Safety

    The underlying purpose of 10 CFR 50.46 is to establish acceptance 
criteria for adequate ECCS performance. By letter dated June 10, 2005, 
the NRC staff issued a safety evaluation (SE) \2\ approving Addendum 1 
to Westinghouse Topical Report WCAP-12610-P-A and CENPD-404-P-A, 
``Optimized ZIRLO<SUP>TM</SUP> (these topical reports are non-publicly 
available because they contain proprietary information),'' wherein the 
NRC staff approved the use of Optimized ZIRLO<SUP>TM</SUP> as a fuel 
cladding material. The NRC staff approved the use of Optimized 
ZIRLO<SUP>TM</SUP> as a fuel cladding material based on: (1) 
Similarities with standard ZIRLO<SUP>TM</SUP>, (2) demonstrated 
material performance, and (3) a commitment to provide irradiated data 
and validate fuel performance models ahead of burnups achieved in batch 
application. The NRC staff's safety evaluation for Optimized 
ZIRLO<SUP>TM</SUP> includes 10 conditions and limitations for its use. 
As previously documented in the NRC staff's review of topical reports 
submitted by Westinghouse Electric Company, LLC (Westinghouse), and 
subject to compliance with the specific conditions of approval 
established therein, the NRC staff finds that the applicability of 
these ECCS acceptance criteria to Optimized ZIRLO<SUP>TM</SUP> has been 
demonstrated by Westinghouse. Ring compression tests performed by 
Westinghouse on Optimized ZIRLO<SUP>TM</SUP> (NRC-reviewed, approved, 
and documented in Appendix B of WCAP-12610-P-A and CENPD-404-P-A, 
Addendum 1-A, ``Optimized ZIRLO<SUP>TM</SUP>'') demonstrate an 
acceptable retention of post-quench ductility up to 10 CFR 50.46 limits 
of 2200 degrees Fahrenheit and 17 percent equivalent clad reacted. 
Furthermore, the NRC staff has concluded that oxidation measurements 
provided by the licensee illustrate that oxide thickness (and 
associated hydrogen pickup) for Optimized ZIRLO<SUP>TM</SUP> at any 
given burnup would be less than both zircaloy-4 and ZIRLO<SUP>TM</SUP>. 
Hence, the NRC staff concludes that Optimized ZIRLO<SUP>TM</SUP> would 
be expected to maintain better post-quench ductility than 
ZIRLO<SUP>TM</SUP>. This finding is further supported by an ongoing 
loss-of-coolant accident (LOCA) research program at Argonne National 
Laboratory, which has identified a strong correlation between cladding 
hydrogen content (due to in-service corrosion) and post-quench 
ductility.
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    \2\ ADAMS Accession No. ML051670408.
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    The underlying purpose of 10 CFR Part 50, Appendix K, Section 
I.A.5, ``Metal-Water Reaction Rate,'' is to ensure that cladding 
oxidation and hydrogen generation are appropriately limited during a 
LOCA and conservatively accounted for in the ECCS evaluation model. 
Appendix K states that the rates of energy release, hydrogen 
concentration, and cladding oxidation from the metal-water reaction 
shall be calculated using the Baker-Just equation. Since the Baker-Just 
equation presumes the use of zircaloy clad fuel, strict application of 
the rule would not permit use of the equation for Optimized 
ZIRLO<SUP>TM</SUP> cladding for determining acceptable fuel 
performance. However, the NRC staff has found that metal-water reaction 
tests performed by Westinghouse on Optimized ZIRLO<SUP>TM</SUP> 
demonstrate conservative reaction rates relative to the Baker-Just 
equation and are bounding for those approved for ZIRLO<SUP>TM</SUP> 
under anticipated operational occurrences and postulated accidents.
    Based on the above, no new accident precursors are created by using 
Optimized ZIRLO<SUP>TM</SUP>; thus, the probability of postulated 
accidents is not increased. Also, based on the above, the consequences 
of postulated accidents are not increased. Therefore, there is no undue 
risk to public health and safety due to using Optimized 
ZIRLO<SUP>TM</SUP>.

Consistent With Common Defense and Security

    The proposed exemption would allow the use of Optimized 
ZIRLO<SUP>TM</SUP> fuel rod cladding material at SURRY. This change to 
the plant configuration has no relation to security issues. Therefore, 
the common defense and security is not impacted by this exemption.

Special Circumstances

    Special circumstances, in accordance with 10 CFR 50.12(a)(2)(ii), 
are present whenever application of the regulation in the particular 
circumstances is not necessary to achieve the underlying purpose of the 
rule. The underlying purpose of 10 CFR 50.46 and Appendix K to 10 CFR 
Part 50 is to establish acceptance criteria for ECCS performance. The 
wording of the regulations in 10 CFR 50.46 and Appendix K is not 
directly applicable to Optimized ZIRLO<SUP>TM</SUP>, even though the 
evaluations above show that the intent of the regulation is met. 
Therefore, since the underlying purposes of 10 CFR 50.46 and Appendix K 
are achieved through the use of Optimized ZIRLO<SUP>TM</SUP> fuel rod 
cladding material, the special circumstances required by 10 CFR 
50.12(a)(2)(ii) for the granting of an exemption from certain 
requirements of 10 CFR 50.46 and Appendix K exist.

4.0 Conclusion

    Accordingly, the Commission has determined that, pursuant to 10 CFR 
50.12, the exemption is authorized by law, will not present an undue 
risk to the public health and safety, and is consistent with the common 
defense and security. Also, special circumstances are present. 
Therefore, the Commission hereby grants VEPCO an exemption from certain 
requirements of 10 CFR 50.46 and Appendix K to 10 CFR Part 50, to allow 
the use of Optimized ZIRLO<SUP>TM</SUP> fuel rod cladding material, for 
SURRY, Unit Nos. 1 and 2.
    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 as published in the Federal Register 
on October 5, 2010 (75 FR 61528).
    This exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 15th day of December 2010.

    For the Nuclear Regulatory Commission.
Joseph G. Giitter,
Director, Division of Operating Reactor Licensing, Office of Nuclear 
Reactor Regulation.
[FR Doc. 2010-32144 Filed 12-21-10; 8:45 am]
BILLING CODE 7590-01-P