[Federal Register Volume 82, Number 123 (Wednesday, June 28, 2017)]
[Notices]
[Pages 29345-29347]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-13517]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-244; NRC-2017-0124]


Exelon Generation Company, LLC; R.E. Ginna Nuclear Power Plant; 
Use of Optimized ZIRLOTM Fuel Rod Cladding

AGENCY: Nuclear Regulatory Commission.

ACTION: Exemption; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing an 
exemption in response to an August 22, 2016, request from Exelon 
Generation Company, LLC (Exelon) in order to use Optimized 
ZIRLOTM Fuel Rod Cladding at the R.E. Ginna Nuclear Power 
Plant (Ginna).

DATES: The exemption was issued on June 19, 2017.

ADDRESSES: Please refer to Docket ID NRC-2017-0124 when contacting the 
NRC about the availability of information regarding this document. You 
may obtain publicly-available information related to this document 
using any of the following methods:
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2017-0124. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions, contact 
the individual listed in the FOR FURTHER INFORMATION CONTACT section of 
this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly-available documents online in the 
ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and 
then select ``Begin Web-based ADAMS Search.'' For problems with ADAMS, 
please contact the NRC's Public Document Room (PDR) reference staff at 
1-800-397-4209, 301-415-4737, or by email to [email protected]. The 
ADAMS accession number for each document referenced (if it is available 
in ADAMS) is provided the first time that it is mentioned in this 
document.
     NRC's PDR: You may examine and purchase copies of public 
documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 
Rockville Pike, Rockville, Maryland 20852.

FOR FURTHER INFORMATION CONTACT: V. Sreenivas, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington DC 
20555-0001; telephone: 301-415-2597, email: [email protected].

SUPPLEMENTARY INFORMATION: 

I. Background

    Exelon Generation Company, LLC is the holder of Renewed Facility 
Operating License No. DPR-18, which authorizes operation of Ginna, a 
pressurized-water reactor. The license provides, among other things, 
that the facility is subject to all rules, regulations, and orders of 
the NRC now or hereafter in effect. The facility is located in Ontario, 
New York, approximately 20 miles northeast of Rochester, New York.

II. Request/Action

    Pursuant to Sec.  50.12 of title 10 of the Code of Federal 
Regulations (10 CFR), ``Specific exemptions,'' the licensee requested, 
by letter dated August 22, 2016 (ADAMS Accession No. ML16236A300), an 
exemption from Sec.  50.46, ``Acceptance criteria for emergency core 
cooling systems [ECCS] for light-water nuclear power reactors,'' and 10 
CFR part 50, appendix K, ``ECCS Evaluation Models,'' to allow the use 
of Optimized ZIRLOTM fuel rod cladding. The regulations in 
Sec.  50.46 contain acceptance criteria for the ECCS for reactors 
fueled with zircaloy or ZIRLOTM fuel rod cladding material. 
In addition, 10 CFR part 50, appendix K, 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 assumes the use of a zirconium alloy different 
than Optimized ZIRLOTM material. Therefore, an exemption to 
Sec.  50.46 and 10 CFR part 50, appendix K is required to support the 
use of Optimized ZIRLOTM fuel rod cladding at Ginna.
    The exemption request relates solely to the specific types of 
cladding material specified in these regulations (i.e., fuel rods with 
Zircaloy or ZIRLO[supreg] cladding). This request will provide for the 
application of the acceptance criteria of Sec.  50.46 and appendix K to 
10 CFR part 50 to fuel assembly designs utilizing Optimized 
ZIRLOTM fuel rod cladding. The NRC staff prepared a separate 
safety evaluation fully addressing Exelon's application for a related 
license amendment.

III. Discussion

    Pursuant to Sec.  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

[[Page 29346]]

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 specific regulation in the particular 
circumstance would not serve, or is not necessary to achieve, the 
underlying purpose of the rule.

A. Authorized by Law

    The exemption would allow the use of Optimized ZIRLOTM 
fuel rod cladding material at Ginna. As stated above, Sec.  50.12 
allows the NRC to grant exemptions from the requirements of 10 CFR part 
50. The NRC staff has determined that granting the licensee's requested 
exemption would 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.

B. No Undue Risk to Public Health and Safety

    The underlying purpose of Sec.  50.46 is to establish acceptance 
criteria for adequate ECCS performance. By letter dated June 10, 2005, 
the NRC staff issued a safety evaluation (ADAMS Accession No 
ML051670408) approving Addendum 1 to Westinghouse Topical Report WCAP-
12610-P-A and CENPD-404-P-A, ``Optimized ZIRLOTM'' (these 
topical reports are not publicly available because they contain 
proprietary information), wherein the NRC staff approved the use of 
Optimized ZIRLOTM as a fuel cladding material. The NRC staff 
approved the use of Optimized ZIRLOTM as a fuel cladding 
material based on: (1) Similarities with standard ZIRLOTM, 
(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 ZIRLOTM includes ten 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 
ZIRLOTM has been demonstrated by Westinghouse. Ring 
compression tests performed by Westinghouse on Optimized 
ZIRLOTM (NRC-reviewed, approved, and documented in Appendix 
B of WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, ``Optimized 
ZIRLOTM'') demonstrate an acceptable retention of post-
quench ductility up to Sec.  50.46 limits of 2,200 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 ZIRLOTM at any given burnup would be less than 
both zircaloy-4 and ZIRLOTM. Hence, the NRC staff concludes 
that Optimized ZIRLOTM would be expected to maintain better 
post-quench ductility than ZIRLOTM. This finding is further 
supported by an ongoing loss-of-coolant accident 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.
    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 
loss-of-coolant accident 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 ZIRLOTM cladding for determining acceptable fuel 
performance. However, the NRC staff has found that metal-water reaction 
tests performed by Westinghouse on Optimized ZIRLOTM 
demonstrate conservative reaction rates relative to the Baker-Just 
equation and are bounding for those approved for ZIRLO\TM\ under 
anticipated operational occurrences and postulated accidents.
    Based on the above, no new accident precursors are created by using 
Optimized ZIRLOTM; 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 
ZIRLOTM.

C. Consistent With the Common Defense and Security

    The proposed exemption would allow the use of Optimized 
ZIRLOTM fuel rod cladding material at Ginna. This change to 
the plant configuration has no relation to security issues. Therefore, 
the common defense and security is not impacted by this exemption.

D. Special Circumstances

    Special circumstances, in accordance with Sec.  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 Sec.  50.46 and appendix K to 10 CFR 
part 50 is to establish acceptance criteria for ECCS performance. The 
wording of the regulations in Sec.  50.46 and appendix K is not 
directly applicable to Optimized ZIRLOTM, even though the 
evaluations above show that the intent of the regulation is met. 
Therefore, since the underlying purposes of Sec.  50.46 and appendix K 
are achieved through the use of Optimized ZIRLOTM fuel rod 
cladding material, the special circumstances required by Sec.  
50.12(a)(2)(ii) for the granting of an exemption from certain 
requirements of Sec.  50.46 and appendix K exist.

E. Environmental Considerations

    The NRC staff determined that the exemption discussed herein meets 
the eligibility criteria for the categorical exclusion set forth in 
Sec.  51.22(c)(9) because it is related to a requirement concerning the 
installation or use of a facility component located within the 
restricted area, as defined in 10 CFR part 20, and the granting of this 
exemption involves: (1) No significant hazards consideration, (2) no 
significant change in the types or a significant increase in the 
amounts of any effluents that may be released offsite, and (3) no 
significant increase in individual or cumulative occupational radiation 
exposure. Therefore, in accordance with Sec.  51.22(b), no 
environmental impact statement or environmental assessment need to be 
prepared in connection with the NRC's consideration of this exemption 
request. The basis for the NRC staff's determination is discussed as 
follows with an evaluation against each of the requirements in Sec.  
51.22(c)(9).
Requirements in Sec.  51.22(c)(9)(i)
    The NRC staff evaluated the issue of no significant hazards 
consideration, using the standards described in Sec.  50.92(c), as 
presented below:
    1. Does the proposed exemption involve a significant increase in 
the probability or consequences of an accident previously evaluated?
    Response: No.
    The proposed change would allow the use of Optimized 
ZIRLOTM clad nuclear fuel in the reactors. The NRC-approved 
topical report WCAP-12610-P-A & CENPD-404-P-A, Addendum 1-A, 
``Optimized ZIRLOTM,'' prepared by

[[Page 29347]]

Westinghouse Electric Company, LLC (Westinghouse), addresses Optimized 
ZIRLOTM and demonstrates that Optimized ZIRLOTM 
has essentially the same properties as currently licensed 
ZIRLO[supreg]. The fuel cladding itself is not an accident initiator 
and does not affect accident probability.
    2. Does the proposed exemption create the possibility of a new or 
different kind of accident from any accident previously evaluated?
    Response: No.
    Use of Optimized ZIRLOTM clad fuel will not result in 
changes in the operation or configuration of the facility. Topical 
Report WCAP-12610-P-A & CENPD-404-P-A, Addendum 1-A, demonstrated that 
the material properties of Optimized ZIRLOTM are similar to 
those of standard ZIRLO[supreg], thus precluding the possibility of the 
fuel cladding becoming an accident initiator and causing a new or 
different type of accident. Therefore, the proposed change does not 
create the possibility of a new or different kind of accident from any 
previously evaluated.
    3. Does the proposed exemption involve a significant reduction in a 
margin of safety?
    Response: No.
    The proposed change will not involve a significant reduction in the 
margin of safety. Topical Report WCAP-12610-P-A & CENPD-404-P-A, 
Addendum 1-A, demonstrated that the material properties of the 
Optimized ZIRLOTM are not significantly different from those 
of standard ZIRLO[supreg]. Optimized ZIRLOTM is expected to 
perform similarly to standard ZIRLO[supreg] for all normal operating 
and accident scenarios, including both loss of coolant accident LOCA) 
and non-LOCA scenarios. For LOCA scenarios, where the slight difference 
is Optimized ZIRLOTM material properties relative to 
standard ZIRLO[supreg] could have some impact on the overall accident 
scenario, plant-specific LOCA analyses using Optimized 
ZIRLOTM properties will demonstrate that the acceptance 
criteria of 10 CFR 50.46 have been satisfied. Therefore, the proposed 
change does not involve a significant reduction in a margin of safety.
    Based on the above, the NRC staff concludes that the proposed 
exemption presents no significant hazards consideration under the 
standards set forth in Sec.  50.92(c), and, accordingly, a finding of 
no significant hazards consideration is justified (i.e., satisfies the 
provisions of Sec.  51.22(c)(9)(i)).
Requirements in Sec.  51.22(c)(9)(ii)
    The proposed exemption would allow the use of Optimized 
ZIRLOTM fuel rod cladding material at Ginna. Optimized 
ZIRLOTM has essentially the same properties are currently 
licensed ZIRLO[supreg]. The use of Optimized ZIRLOTM fuel 
rod cladding material will not significantly change the types of 
effluents that may be released offsite or significantly increase the 
amount of effluents that may be released offsite. Therefore, the 
provisions of Sec.  51.22(c)(9)(ii) are satisfied.
Requirements in Sec.  51.22(c)(9)(iii)
    The proposed exemption would allow the use of Optimized 
ZIRLOTM fuel rod cladding material at Ginna. Optimized 
ZIRLOTM has essentially the same properties are currently 
licensed ZIRLO[supreg]. The use of Optimized ZIRLOTM fuel 
rod cladding material at Ginna will not significantly increase 
individual occupational radiation exposure or significantly increase 
cumulative occupational radiation exposure. Therefore, the provisions 
of Sec.  51.22(c)(9)(iii) are satisfied.
Conclusion
    Based on the above, the NRC staff concludes that the proposed 
exemption meets the eligibility criteria for the categorical exclusion 
set forth in Sec.  51.22(c)(9). Therefore, in accordance with Sec.  
51.22(b), no environmental impact statement or environmental assessment 
need to be prepared in connection with the NRC's proposed issuance of 
this exemption.

IV. Conclusion

    Accordingly, the Commission has determined that, pursuant to Sec.  
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 Exelon an exemption from 
certain requirements of Sec.  50.46 and 10 CFR part 50, appendix K, to 
allow the use of Optimized ZIRLOTM fuel rod cladding 
material at Ginna.

    Dated at Rockville, Maryland, this 19th day of June 2017.

    For the Nuclear Regulatory Commission.
MaryJane Ross-Lee,
Acting Director, Division of Operating Reactor Licensing, Office of 
Nuclear Reactor Regulation.
[FR Doc. 2017-13517 Filed 6-27-17; 8:45 am]
 BILLING CODE 7590-01-P