[Federal Register Volume 85, Number 46 (Monday, March 9, 2020)]
[Notices]
[Pages 13676-13678]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-04767]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. STN 50-528, STN 50-529, and STN 50-530; NRC-2020-0069]
Arizona Public Service Company; Palo Verde Nuclear Generating
Station, Units 1, 2, and 3
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 a July 6, 2018, request, as supplemented by
letters dated October 18, 2018; March 1, 2019; May 17, 2019; October 4,
2019; November 26, 2019; and December 19, 2019, from Arizona Public
Service Company (the licensee) in order to use Framatome M5[supreg]
alloy as a fuel rod cladding material at Palo Verde Nuclear Generating
Station, Units 1, 2, and 3.
DATES: The exemption was issued on March 4, 2020.
ADDRESSES: Please refer to Docket ID NRC-2020-0069 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 Website: Go to http://www.regulations.gov and search for Docket ID NRC-2020-0069. Address
questions about NRC docket IDs in Regulations.gov to Jennifer Borges;
telephone: 301-287-9127; 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 ``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 in this
[[Page 13677]]
document (if that document 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: Siva P. Lingam, Office of Nuclear
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC
20555-0001; telephone: 301-415-1564, email: [email protected].
SUPPLEMENTARY INFORMATION: The text of the exemption is attached.
Dated at Rockville, Maryland, this 4th day of March, 2020.
For the Nuclear Regulatory Commission.
Siva P. Lingam,
Project Manager, Plant Licensing Branch IV, Division of Operating
Reactor Licensing, Office of Nuclear Reactor Regulation.
Attachment: Exemption
Nuclear Regulatory Commission
Docket Nos. STN 50-528, STN 50-529, and STN 50-530 Arizona Public
Service Company Palo Verde Nuclear Generating Station, Units 1, 2, and
3 Exemption
I. Background
Arizona Public Service Company (APS, the licensee) is the holder of
Renewed Facility Operating License Nos. NPF-41, NPF-51, and NPF-74,
which authorizes operation of Palo Verde Nuclear Generating Station,
Units 1, 2, and 3 (Palo Verde), respectively. 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)
now or hereafter in effect. The facility consists of a pressurized-
water reactor (PWR) located in Maricopa County, Arizona.
By application dated July 6, 2018, as supplemented by letters dated
October 18, 2018; March 1, 2019; May 17, 2019; October 4, 2019;
November 26, 2019; and December 19, 2019 (Agencywide Documents Access
and Management System (ADAMS) Accession Nos. ML18187A417, ML18296A466,
ML19060A298, ML19137A118, ML19277J457, ML19331A361, and ML19353C038,
respectively), APS, pursuant to Title 10 of the Code of Federal
Regulations (10 CFR) Section 50.12, ``Specific exemptions,'' 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 10 CFR part 50, Appendix K, ``ECCS
Evaluation Models,'' for Palo Verde. Since these regulations
specifically refer only to zircaloy and ZIRLOTM, an
exemption would be required to apply them to fuel clad with other
materials, such as Framatome M5[supreg] zirconium alloy.\1\ Therefore,
APS has requested such an exemption to support transition to the
Framatome M5[supreg] alloy cladding. The proposed request would not
exempt Palo Verde from the requirements of 10 CFR 50.46 or 10 CFR part
50, Appendix K regarding acceptance criteria, evaluation model features
and documentation, reporting of changes or errors, etc.
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\1\ HTP and M5[supreg]'' are trademarks or registered
trademarks of Framatome, Inc. (formerly AREVA Inc.).
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The submittal from APS described above also contains the fuel
transition license amendment request that is necessary to support batch
loading of Framatome Advanced Combustion Engineering (CE) 16x16 High
Thermal Performance (HTPTM) fuel. This exemption is specific
to the Framatome M5[supreg] cladding material exemption request only.
The fuel transition and associated technical specification changes are
subject to a concurrent review that is being documented in the safety
evaluation (SE) with the license amendments (ADAMS Accession No.
ML20031C947).
Precedent exemptions have also been approved for other CE plants
including St. Lucie Plant, Unit Nos. 1 and 2 (ADAMS Accession Nos.
ML14064A125 and ML16015A286, respectively).
II. Request/Action
By application dated July 6, 2018, as supplemented by letters dated
October 18, 2018, and March 1, 2019; May 17, 2019; October 4, 2019;
November 26, 2019; and December 19, 2019, APS, pursuant to 10 CFR
50.12, requested an exemption from the requirements of 10 CFR 50.46 and
Appendix K to 10 CFR part 50. The proposed exemption request would
permit the application of 10 CFR 50.46 and Appendix K to 10 CFR part 50
to fuel rods cladded with Framatome M5[supreg] alloy at Palo Verde.
Since the requirements in 10 CFR 50.46 and Appendix K to 10 CFR part 50
are predicated upon the use of fuel clad with zircaloy or
ZIRLOTM alloy, an exemption is necessary to apply these
requirements to fuel rods clad with Framatome M5[supreg] alloy.
The technical basis supporting the use of fuel clad with M5[supreg]
in PWRs is documented primarily in Topical Report BAW-10227-P-A,
Revision 1, ``Evaluation of Advanced Cladding and Structural Material
(M5[supreg]) in PWR Reactor Fuel,'' dated June 2003 (ADAMS Accession
No. ML15162B043). This topical report describes Framatome's evaluation
supporting the use of the M5[supreg] alloy in PWR fuel assemblies as a
replacement for Zircaloy-4. This topical report discusses fundamental
material properties of M5[supreg], as well as its behavior under normal
operation, anticipated transients, and postulated accident conditions.
III. Discussion
The regulation in Section 50.46(a)(1)(i) of 10 CFR states, in part:
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 loss-of-coolant accidents conforms
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 loss-of-coolant accidents of different sizes, locations,
and other properties sufficient to provide assurance that the most
severe postulated loss-of-coolant accidents are calculated.
Since 10 CFR 50.46 specifically refers to fuel with zircaloy or
ZIRLOTM cladding, its application to fuel clad with
materials other than zircaloy or ZIRLOTM requires an
exemption from this section of the regulations.
The regulation in paragraph I.A.5, ``Metal--Water Reaction Rate,''
of 10 CFR part 50, Appendix K, states, in part:
The rate of energy release, hydrogen generation, and cladding
oxidation from the metal/water reaction shall be calculated using
the Baker-Just equation (Baker, L., Just, L.C., ``Studies of Metal
Water Reactions at High Temperatures, III. Experimental and
Theoretical Studies of the Zirconium-Water Reaction,'' ANL-6548,
page 7, May 1962).
The requirement for using the Baker-Just equation in Appendix K-
conformant loss-of-coolant accident evaluation models presumes use of
zircaloy or ZIRLOTM clad fuel rods. Therefore, application
of 10 CFR part 50, Appendix K to cladding materials other than zircaloy
or ZIRLOTM also requires an exemption.
The exemption request from APS relates solely to the particular
types of fuel cladding materials specified in these regulations. As
written, the regulations presume use of zircaloy or ZIRLOTM
cladding. Thus, an exemption is necessary to apply 10 CFR 50.46 and 10
CFR part 50, Appendix K to other cladding materials such as M5[supreg].
The proposed request would not exempt Palo Verde from any other
requirements of 10 CFR 50.46 or 10 CFR part 50,
[[Page 13678]]
Appendix K regarding acceptance criteria, evaluation model features and
documentation, reporting of changes or errors, etc.
Section 50.12 of 10 CFR states that the Commission may grant
exemptions from requirements of the regulations in 10 CFR part 50 for
reasons, which are (1) the exemption is authorized by law, (2) the
exemption will not present an undue risk to the public health and
safety, (3) the exemption is consistent with the common defense and
security, and (4) special circumstances, as defined in 10 CFR
50.12(a)(2), are present. The licensee's submittal identifies in
particular that the special circumstance associated with this exemption
request is that restricting application of 10 CFR 50.46 and 10 CFR part
50, Appendix K to fuels clad with only zircaloy or ZIRLOTM
is not necessary to achieve the underlying purpose of these
regulations.
A. The Exemption is Authorized by Law
The NRC has the authority under 10 CFR 50.12 to grant exemptions
from the requirements of Part 50 upon demonstration of proper
justification. The fuel that will be irradiated at Palo Verde is clad
with a zirconium-based alloy that is not expressly within the scope of
10 CFR 50.46 and 10 CFR part 50, Appendix K. However, the NRC staff
considers the acceptance criteria and methods of these regulations
applicable to M5[supreg], and the licensee will ensure that these
regulations are satisfied for operation with fuel clad with M5[supreg].
Therefore, the exemption is authorized by law.
B. The Exemption Presents No Undue Risk to Public Health and Safety
The NRC-approved Topical Report BAW-10227-P-A, which concerns the
properties of the M5[supreg] alloy, provides assurance that predicted
chemical, thermal, and mechanical characteristics of M5[supreg] alloy
cladding are acceptable under normal operation, anticipated transients,
and postulated accidents. The NRC staff further found that the
acceptance criteria and analytical methods from 10 CFR 50.46 and 10 CFR
part 50, Appendix K provide acceptable safety margins for fuel clad
with M5[supreg] that are consistent with those the NRC has established
for zircaloy and ZIRLO\TM\. Reload cores involving M5[supreg] cladding
will continue to be subject to the operating limits specified in the
technical specifications and core operating limits report. Thus,
granting this exemption request will not pose undue risk to public
health and safety.
C. The Exemption Is Consistent With the Common Defense and Security
The proposed exemption will allow the licensee to use an enhanced
fuel rod cladding material relative to the zircaloy material for which
the requirements of 10 CFR 50.46 and 10 CFR part 50, Appendix K were
originally established. In addition to its review of the exemption
request described in this SE, the NRC staff has further evaluated all
licensing-basis changes necessary to support loading fuel clad with
M5[supreg] in a separate SE and documented the basis for their
acceptability. Based on these reviews, the NRC staff concludes that the
use of M5[supreg] fuel rod cladding at Palo Verde will not
significantly affect plant operations and is therefore consistent with
the common defense and security.
D. Special Circumstances
Neither 10 CFR 50.46 nor 10 CFR part 50, Appendix K explicitly
applies to fuel clad with M5[supreg]. However, the underlying purpose
of 10 CFR 50.46 and 10 CFR part 50, Appendix K is to provide
requirements capable of ensuring adequate core cooling following the
most limiting postulated loss-of-coolant accident. As discussed above,
Framatome has demonstrated in an NRC-approved topical report (i.e.,
BAW-10227-P-A) that application of the acceptance criteria and
analytical methods required in 10 CFR 50.46 and 10 CFR part 50,
Appendix K to fuel clad with M5[supreg] is acceptable. Normal core
reload safety analyses will further confirm on a cycle-specific basis
that there is no adverse impact on ECCS performance for Palo Verde.
Therefore, strict application of the material-specific requirements for
fuel cladding in 10 CFR 50.46 and 10 CFR part 50, Appendix K is not
necessary to achieve the underlying purpose of ensuring adequate core
cooling in this instance. Furthermore, granting an exemption to allow
application of the balance of these regulations to fuel clad with
M5[supreg] at Palo Verde would be consistent with the underlying
regulatory purpose.
E. Supplemental Information
For more technical details, refer to the SE associated with this
exemption under ADAMS Accession No. ML20022A109 (Enclosure 2).
F. Environmental Considerations
The NRC staff determined that the exemption discussed herein meets
the eligibility criteria for the categorical exclusion set forth in 10
CFR 51.22(c)(9) because it is related to a requirement concerning the
installation or use of facility components located within the
restricted area, as defined in 10 CFR part 20, and the granting of this
exemption involves: (i) No significant hazards consideration, (ii) no
significant change in the types or a significant increase in the
amounts of any effluents that may be released offsite, and (iii) no
significant increase in individual or cumulative occupational radiation
exposure. Therefore, in accordance with 10 CFR 51.22(b), no
environmental impact statement or environmental assessment need be
prepared in connection with the NRC's consideration of this exemption
request.
IV. Conclusions
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 APS an exemption from the
requirements of 10 CFR 50.46 and 10 CFR part 50, Appendix K, to allow
the use of Framatome M5[supreg] alloy fuel rod cladding material at
Palo Verde, Units 1, 2, and 3. As stated above, this exemption relates
solely to the cladding material specified in these regulations.
Dated at Rockville, Maryland, this 4th day of March 2020.
For the Nuclear Regulatory Commission.
Craig G. Erlanger,
Director, Division of Operating Reactor Licensing, Office of Nuclear
Reactor Regulation.
[FR Doc. 2020-04767 Filed 3-6-20; 8:45 am]
BILLING CODE 7590-01-P