Carolina Power & Light Company; H. B. Robinson Steam Electric Plant, Unit 2; Exemption, 68512-68514 [2011-28610]
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68512
Federal Register / Vol. 76, No. 214 / Friday, November 4, 2011 / Notices
Authorized by Law
This exemption would allow the use
of Optimized ZIRLO TM fuel rod
cladding material at STP, Units 1 and 2.
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.
mstockstill on DSK4VPTVN1PROD with NOTICES
No Undue Risk to Public Health and
Safety
The underlying purpose of 10 CFR
50.46 is to establish acceptance criteria
for ECCS performance. Westinghouse
topical reports WCAP–12610–P–A and
CENPD–404–P–A, Addendum 1–A,
‘‘Optimized ZIRLOTM,’’ dated July 2006,
contain the justification to use
Optimized ZIRLOTM fuel rod cladding
material in addition to Zircaloy-4 and
ZIRLOTM (these topical reports are nonpublicly available because they contain
proprietary information). The NRC staff
approved the use of these topical
reports, subject to the conditions stated
in the NRC staff’s safety evaluation for
each topical report. Ring compression
tests performed by Westinghouse on
Optimized ZIRLOTM were reviewed and
approved by the NRC staff (ADAMS
Accession No. ML062080569), and
demonstrate an acceptable retention of
post-quench ductility up to the 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
ZIRLOTM at any given burnup would be
less than that for both zircaloy and
ZIRLOTM (ADAMS Accession No.
ML073130555). Hence, the NRC staff
concludes that Optimized ZIRLOTM
would be expected to maintain
improved post-quench ductility over
ZIRLOTM. Finally, the licensee stated
that Westinghouse will perform an
evaluation to ensure that the Optimized
ZIRLOTM fuel rods continue to satisfy 10
CFR 50.46 acceptance criteria utilizing
currently NRC-approved loss-of-coolant
accident (LOCA) models and methods.
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 of
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Jkt 226001
10 CFR part 50 requires that the BakerJust equation be used in the ECCS
evaluation model to determine the rate
of energy release, cladding oxidation,
and hydrogen generation. Since the use
of 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.
Westinghouse has demonstrated that the
Baker-Just model is conservative in all
post-LOCA scenarios with respect to the
use of the Optimized ZIRLOTM
advanced alloy as a fuel cladding
material.
The NRC-approved topical reports
have demonstrated that predicted
chemical, thermal, and mechanical
characteristics of the Optimized
ZIRLOTM alloy cladding are bounded by
those approved for ZIRLOTM under
anticipated operational occurrences and
postulated accidents. Reload cores are
required to be operated in accordance
with the operating limits specified in
the technical specifications and the core
operating limits report.
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.
Consistent With Common Defense and
Security
The proposed exemption would allow
the use of Optimized ZIRLOTM fuel rod
cladding material at STP, Units 1 and 2.
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 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 ZIRLOTM, 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
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Sfmt 4703
Optimized ZIRLOTM fuel rod cladding
material, the special circumstances
required by 10 CFR 50.12(a)(2)(ii) for the
granting of an exemption 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 the
licensee an exemption from the
requirements of 10 CFR 50.46 and
Appendix K to 10 CFR part 50, to allow
the use of Optimized ZIRLOTM fuel rod
cladding material at STP, Units 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 and published an
environmental assessment for this
exemption on October 11, 2011 (76 FR
62861).
This exemption is effective upon
issuance.
Dated at Rockville, Maryland, this 27th day
of October 2011.
For the Nuclear Regulatory Commission.
Michele G. Evans,
Director, Division of Operating Reactor
Licensing, Office of Nuclear Reactor
Regulation.
[FR Doc. 2011–28608 Filed 11–3–11; 8:45 am]
BILLING CODE 7590–01–P
NUCLEAR REGULATORY
COMMISSION
[NRC–2010–0062; Docket No. 50–261]
Carolina Power & Light Company; H.
B. Robinson Steam Electric Plant, Unit
2; Exemption
1.0
Background
Carolina Power & Light Company (the
licensee) is the holder of Renewed
Facility Operating License No. DPR–23,
which authorizes operation of the H. B.
Robinson Steam Electric Plant
(HBRSEP), Unit 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 one pressurized-water
reactor located in New Hill, North
Carolina.
2.0
Request/Action
Title 10 of the Code of Federal
Regulations (10 CFR), 50.46,
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Federal Register / Vol. 76, No. 214 / Friday, November 4, 2011 / Notices
‘‘Acceptance criteria for emergency core
cooling systems for light-water nuclear
power reactors,’’ paragraph (a)(1)(i)
provides requirements for reactors
containing uranium oxide fuel pellets
clad in either zircaloy or ZIRLO.
Additionally, Appendix K to 10 CFR
part 50, ‘‘ECCS [Emergency Core
Cooling System] Evaluation Models,’’
specifies the use of zircaloy or ZIRLO
fuel cladding when doing calculations
for energy release, cladding oxidation,
and hydrogen generation after a
postulated loss-of-coolant accident.
Therefore, both of these regulations
either state or assume that either
zircaloy or ZIRLO is used as the fuel rod
cladding material.
By letter dated October 19, 2010
(Agencywide Documents Access and
Management System (ADAMS)
Accession No. ML102980142), the
licensee requested an exemption from
the requirements of 10 CFR 50.46 and
Appendix K to 10 CFR part 50 to allow
the use of fuel rods clad with AREVA’s
M5 alloy. The advanced zirconiumbased M5 alloy is a proprietary alloy
and chemically different from zircaloy
or ZIRLO fuel cladding materials, which
are approved for use. The exemption
request related solely to the specific
types of cladding material specified in
these regulations. As written, the
regulations presume the use of zircaloy
or ZIRLO fuel rod cladding. Thus, an
exemption from the requirements of 10
CFR 50.46 and Appendix K to 10 CFR
part 50 is needed to support transition
to the AREVA fuel design with
advanced zirconium-based M5 alloy at
HBRSEP Unit 2.
mstockstill on DSK4VPTVN1PROD with NOTICES
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. The requested exemption to
allow the use of M5 advanced
zirconium alloy rather than zircaloy or
ZIRLO for fuel cladding material for
reloads at HBRSEP, Unit 2, satisfies
these requirements as described below.
Authorized by Law
This exemption would allow the use
of M5 advanced alloy, in lieu of zircaloy
or ZIRLO, for fuel rod cladding in fuel
assemblies at HBRSEP, Unit 2. As stated
above, 10 CFR 50.12 allows the NRC to
grant exemptions from the requirements
of 10 CFR 50.46 and Appendix K to 10
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17:06 Nov 03, 2011
Jkt 226001
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 ECCS performance. In the approved
topical report BAW–10227(P)(A),
Revision 1, ‘‘Evaluation of Advanced
Cladding and Structural Material (M5)
in PWR Reactor Fuel,’’ dated June 18,
2003, Framatome ANP demonstrated
that the effectiveness of the ECCS will
not be affected by a change from
zircaloy fuel rod cladding to M5 fuel rod
cladding. The analysis described in the
topical report also demonstrated that the
ECCS acceptance criteria applied to
reactors fueled with zircaloy clad fuel
are also applicable to reactors fueled
with M5 fuel rod cladding.
The NRC staff’s review and approval
of topical report BAW–10227(P)(A),
Revision1 addressed all of the important
aspects of M5 with respect to ECCS
performance requirements: (1)
Applicability of 10 CFR 50.46(b) fuel
acceptance criteria; (2) M5 material
properties including fuel rod ballooning
and rupture strains; and (3) steam
oxidation kinetics and applicability of
Baker-Just weight gain correlation. A
subsequent NRC-approved topical
report, BAW–10240P–A, ‘‘Incorporation
of M5 Properties in Framatome ANP
Approved Methods,’’ further addressed
M5 material properties with respect to
the loss-of-coolant accident (LOCA)
applications.
Appendix K, paragraph I.A.5, of 10
CFR part 50 ensures that cladding
oxidation and hydrogen generation are
appropriately limited during a LOCA,
and conservatively accounted for in the
ECCS evaluation model. Appendix K
requires that the Baker-Just equation be
used in the ECCS evaluation model to
determine the rate of energy release,
cladding oxidation, and hydrogen
generation. In topical report BAW–
10227(P)(A), Revision 1, Framatome
ANP demonstrated that the Baker-Just
model is conservative in the evaluated
post-LOCA scenarios with respect to the
use of the M5 advanced alloy as a fuel
rod cladding material, and that the
amount of hydrogen generated in an
M5-clad core during a LOCA will
remain within the HBRSEP, Unit No. 2,
design basis.
The M5 alloy is proprietary
zirconium-based alloy comprised of
primarily zirconium (∼99 percent) and
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Fmt 4703
Sfmt 4703
68513
niobium (∼1 percent). The elimination
of tin has resulted in superior corrosion
resistance and reduced irradiationinduced growth relative to both
standard zircaloy (1.7 percent tin) and
low-tin zircaloy (1.2 percent tin). The
addition of niobium increases ductility,
which is desirable to avoid brittle
failures.
The NRC staff has reviewed the
advanced cladding and structural
material, M5, for pressurized-water
reactor fuel mechanical designs as
described in BAW–10227(P)(A),
Revision 1. In the safety evaluation for
this topical report, the NRC staff
concluded that, to the extent and
limitations specified in the staff’s
evaluation, the properties of M5 and
mechanical design methodology are
acceptable for referencing in fuel reload
licensing applications.
Based on the above, no new accident
precursors are created by the use of M5
fuel cladding at HBRSEP, Unit 2; 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.
Consistent With Common Defense and
Security
The proposed exemption would allow
the use of M5 advanced alloy, in lieu of
zircaloy or ZIRLO, for fuel rod cladding
in fuel assemblies at HBRSEP, Unit 2.
The M5 fuel rod cladding is similar in
design to the current cladding material
used at HBRSEP, Unit 2. This change in
cladding material will not result in any
changes to the security aspects
associated with the control of special
nuclear material. The change in
cladding material is unrelated to other
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, are present
whenever application of the regulation
in the particular circumstances would
not serve the underlying purpose of the
rule, or is not necessary to achieve the
underlying purpose of the rule.
The underlying purpose of 10 CFR
50.46 is to ensure that nuclear power
facilities have adequately demonstrated
the cooling performance of their ECCS.
As discussed above, topical report
BAW–10227(P)(A), Revision 1
concluded that the effectiveness of the
ECCS will not be affected by a change
from zircaloy fuel rod cladding to M5
fuel rod cladding and also demonstrated
that the ECCS acceptance criteria
E:\FR\FM\04NON1.SGM
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68514
Federal Register / Vol. 76, No. 214 / Friday, November 4, 2011 / Notices
applied to reactors fueled with zircaloy
clad fuel are also applicable to reactors
fueled with M5 fuel rod cladding.
The underlying purpose of 10 CFR
part 50, appendix K, paragraph I.A.5 is
to ensure that cladding oxidation and
hydrogen generation are appropriately
limited during a LOCA and
conservatively accounted for in the
ECCS evaluation model. Specifically,
Appendix K requires that the Baker-Just
equation be used in the ECCS evaluation
model to determine the rate of energy
release, cladding oxidation, and
hydrogen generation. Topical Report
BAW–10227(P)(A), Revision 1,
demonstrated that the Baker-Just model
is conservative in the evaluated postLOCA scenarios with respect to the use
of the M5 advanced alloy as a fuel rod
cladding material.
Based on the above, the underlying
purpose of 10 CFR 50.46 and 10 CFR
part 50, Appendix K is still met and
literal compliance is not necessary for
use of M5 fuel rod cladding. Therefore,
the special circumstances required by
10 CFR 50.12 for the granting of an
exemption from 10 CFR 50.46 and
Appendix K of 10 CFR part 50 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 the
licensee an exemption from the
requirements of 10 CFR 50.46 and
Appendix K of 10 CFR part 50.
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 (October 26, 2011;
76 FR 6633). This exemption is effective
upon issuance.
Dated at Rockville, Maryland this 31st day
of October 2011.
For the Nuclear Regulatory Commission.
Michele G. Evans,
Director, Division of Operating Reactor
Licensing, Office of Nuclear Reactor
Regulation.
[FR Doc. 2011–28610 Filed 11–3–11; 8:45 am]
BILLING CODE 7590–01–P
NUCLEAR REGULATORY
COMMISSION
Request for a License To Export
Reactor Components
Pursuant to 10 CFR 110.70 (b) ‘‘Public
Notice of Receipt of an Application,’’
please take notice that the Nuclear
Regulatory Commission (NRC) has
received the following request for an
export license. Copies of the request are
available electronically through ADAMS
and can be accessed through the Public
Electronic Reading Room (PERR) link
https://www.nrc.gov/reading-rm.html at
the NRC Homepage.
A request for a hearing or petition for
leave to intervene may be filed within
thirty days after publication of this
notice in the Federal Register. Any
request for hearing or petition for leave
to intervene shall be served by the
requestor or petitioner upon the
applicant, the office of the General
Counsel, U.S. Nuclear Regulatory
Commission, Washington, DC 20555;
the Secretary, U.S. Nuclear Regulatory
Commission, Washington, DC 20555;
and the Executive Secretary, U.S.
Department of State, Washington, DC
20520.
A request for a hearing or petition for
leave to intervene may be filed with the
NRC electronically in accordance with
NRC’s E-Filing rule promulgated in
August 2007, 72 Fed. Reg. 49139 (Aug.
28, 2007). Information about filing
electronically is available on the NRC’s
public Web site at https://www.nrc.gov/
site-help/e-submittals.html. To ensure
timely electronic filing, at least 5 (five)
days prior to the filing deadline, the
petitioner/requestor should contact the
Office of the Secretary by email at
HEARINGDOCKET@NRC.GOV, or by
calling (301) 415–1677, to request a
digital ID certificate and allow for the
creation of an electronic docket.
In addition to a request for hearing or
petition for leave to intervene, written
comments, in accordance with 10 CFR
110.81, should be submitted within
thirty (30) days after publication of this
notice in the Federal Register to Office
of the Secretary, U.S. Nuclear
Regulatory Commission, Washington,
DC 20555, Attention: Rulemaking and
Adjudications
The information concerning this
application for an export license
follows.
NRC Export License Application
DESCRIPTION OF EQUIPMENT
Name of applicant/date of
application/date received/
application Number/docket Number
Material type
Westinghouse Electric Company
LLC, August 18, 2011, October
6, 2011, XR174, 11005963.
Complete reactor control rod system and associated equipment.
Total quantity
12
End use
Perform seismic testing necessary
for qualification of AP1000 (design) nuclear reactors.
POSTAL REGULATORY COMMISSION
[FR Doc. 2011–28617 Filed 11–3–11; 8:45 am]
mstockstill on DSK4VPTVN1PROD with NOTICES
For the Nuclear Regulatory Commission.
Dated this 27th day of October 2011 at
Rockville, Maryland.
Stephen Dembek,
Acting Deputy Director, Office of
International Programs.
ACTION:
[Docket No. A2012–32; Order No. 938]
Post Office Closing
Postal Regulatory Commission.
Notice.
AGENCY:
BILLING CODE 7590–01–P
This document informs the
public that an appeal of the closing of
the Barronett, Wisconsin post office has
been filed. It identifies preliminary
steps and provides a procedural
schedule. Publication of this document
will allow the Postal Service,
SUMMARY:
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19:03 Nov 03, 2011
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Destination
China.
petitioners, and others to take
appropriate action.
DATES: November 9, 2011:
Administrative record due (from Postal
Service); November 25, 2011, 4:30 p.m.,
Eastern Time: Deadline for notices to
intervene. See the Procedural Schedule
in the SUPPLEMENTARY INFORMATION
section for other dates of interest.
ADDRESSES: Submit comments
electronically by accessing the ‘‘Filing
Online’’ link in the banner at the top of
the Commission’s Web site (https://
www.prc.gov) or by directly accessing
the Commission’s Filing Online system
E:\FR\FM\04NON1.SGM
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]]>Agencies
[Federal Register Volume 76, Number 214 (Friday, November 4, 2011)]
[Notices]
[Pages 68512-68514]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-28610]
-----------------------------------------------------------------------
NUCLEAR REGULATORY COMMISSION
[NRC-2010-0062; Docket No. 50-261]
Carolina Power & Light Company; H. B. Robinson Steam Electric
Plant, Unit 2; Exemption
1.0 Background
Carolina Power & Light Company (the licensee) is the holder of
Renewed Facility Operating License No. DPR-23, which authorizes
operation of the H. B. Robinson Steam Electric Plant (HBRSEP), Unit 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 one pressurized-water reactor located in New Hill,
North Carolina.
2.0 Request/Action
Title 10 of the Code of Federal Regulations (10 CFR), 50.46,
[[Page 68513]]
``Acceptance criteria for emergency core cooling systems for light-
water nuclear power reactors,'' paragraph (a)(1)(i) provides
requirements for reactors containing uranium oxide fuel pellets clad in
either zircaloy or ZIRLO. Additionally, Appendix K to 10 CFR part 50,
``ECCS [Emergency Core Cooling System] Evaluation Models,'' specifies
the use of zircaloy or ZIRLO fuel cladding when doing calculations for
energy release, cladding oxidation, and hydrogen generation after a
postulated loss-of-coolant accident. Therefore, both of these
regulations either state or assume that either zircaloy or ZIRLO is
used as the fuel rod cladding material.
By letter dated October 19, 2010 (Agencywide Documents Access and
Management System (ADAMS) Accession No. ML102980142), the licensee
requested an exemption from the requirements of 10 CFR 50.46 and
Appendix K to 10 CFR part 50 to allow the use of fuel rods clad with
AREVA's M5 alloy. The advanced zirconium-based M5 alloy is a
proprietary alloy and chemically different from zircaloy or ZIRLO fuel
cladding materials, which are approved for use. The exemption request
related solely to the specific types of cladding material specified in
these regulations. As written, the regulations presume the use of
zircaloy or ZIRLO fuel rod cladding. Thus, an exemption from the
requirements of 10 CFR 50.46 and Appendix K to 10 CFR part 50 is needed
to support transition to the AREVA fuel design with advanced zirconium-
based M5 alloy at HBRSEP Unit 2.
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. The requested exemption to
allow the use of M5 advanced zirconium alloy rather than zircaloy or
ZIRLO for fuel cladding material for reloads at HBRSEP, Unit 2,
satisfies these requirements as described below.
Authorized by Law
This exemption would allow the use of M5 advanced alloy, in lieu of
zircaloy or ZIRLO, for fuel rod cladding in fuel assemblies at HBRSEP,
Unit 2. As stated above, 10 CFR 50.12 allows the NRC to grant
exemptions from the requirements of 10 CFR 50.46 and Appendix K to 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 ECCS performance. In the approved topical report BAW-
10227(P)(A), Revision 1, ``Evaluation of Advanced Cladding and
Structural Material (M5) in PWR Reactor Fuel,'' dated June 18, 2003,
Framatome ANP demonstrated that the effectiveness of the ECCS will not
be affected by a change from zircaloy fuel rod cladding to M5 fuel rod
cladding. The analysis described in the topical report also
demonstrated that the ECCS acceptance criteria applied to reactors
fueled with zircaloy clad fuel are also applicable to reactors fueled
with M5 fuel rod cladding.
The NRC staff's review and approval of topical report BAW-
10227(P)(A), Revision1 addressed all of the important aspects of M5
with respect to ECCS performance requirements: (1) Applicability of 10
CFR 50.46(b) fuel acceptance criteria; (2) M5 material properties
including fuel rod ballooning and rupture strains; and (3) steam
oxidation kinetics and applicability of Baker-Just weight gain
correlation. A subsequent NRC-approved topical report, BAW-10240P-A,
``Incorporation of M5 Properties in Framatome ANP Approved Methods,''
further addressed M5 material properties with respect to the loss-of-
coolant accident (LOCA) applications.
Appendix K, paragraph I.A.5, of 10 CFR part 50 ensures that
cladding oxidation and hydrogen generation are appropriately limited
during a LOCA, and conservatively accounted for in the ECCS evaluation
model. Appendix K requires that the Baker-Just equation be used in the
ECCS evaluation model to determine the rate of energy release, cladding
oxidation, and hydrogen generation. In topical report BAW-10227(P)(A),
Revision 1, Framatome ANP demonstrated that the Baker-Just model is
conservative in the evaluated post-LOCA scenarios with respect to the
use of the M5 advanced alloy as a fuel rod cladding material, and that
the amount of hydrogen generated in an M5-clad core during a LOCA will
remain within the HBRSEP, Unit No. 2, design basis.
The M5 alloy is proprietary zirconium-based alloy comprised of
primarily zirconium (~99 percent) and niobium (~1 percent). The
elimination of tin has resulted in superior corrosion resistance and
reduced irradiation-induced growth relative to both standard zircaloy
(1.7 percent tin) and low-tin zircaloy (1.2 percent tin). The addition
of niobium increases ductility, which is desirable to avoid brittle
failures.
The NRC staff has reviewed the advanced cladding and structural
material, M5, for pressurized-water reactor fuel mechanical designs as
described in BAW-10227(P)(A), Revision 1. In the safety evaluation for
this topical report, the NRC staff concluded that, to the extent and
limitations specified in the staff's evaluation, the properties of M5
and mechanical design methodology are acceptable for referencing in
fuel reload licensing applications.
Based on the above, no new accident precursors are created by the
use of M5 fuel cladding at HBRSEP, Unit 2; 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.
Consistent With Common Defense and Security
The proposed exemption would allow the use of M5 advanced alloy, in
lieu of zircaloy or ZIRLO, for fuel rod cladding in fuel assemblies at
HBRSEP, Unit 2. The M5 fuel rod cladding is similar in design to the
current cladding material used at HBRSEP, Unit 2. This change in
cladding material will not result in any changes to the security
aspects associated with the control of special nuclear material. The
change in cladding material is unrelated to other 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, are present
whenever application of the regulation in the particular circumstances
would not serve the underlying purpose of the rule, or is not necessary
to achieve the underlying purpose of the rule.
The underlying purpose of 10 CFR 50.46 is to ensure that nuclear
power facilities have adequately demonstrated the cooling performance
of their ECCS. As discussed above, topical report BAW-10227(P)(A),
Revision 1 concluded that the effectiveness of the ECCS will not be
affected by a change from zircaloy fuel rod cladding to M5 fuel rod
cladding and also demonstrated that the ECCS acceptance criteria
[[Page 68514]]
applied to reactors fueled with zircaloy clad fuel are also applicable
to reactors fueled with M5 fuel rod cladding.
The underlying purpose of 10 CFR part 50, appendix K, paragraph
I.A.5 is to ensure that cladding oxidation and hydrogen generation are
appropriately limited during a LOCA and conservatively accounted for in
the ECCS evaluation model. Specifically, Appendix K requires that the
Baker-Just equation be used in the ECCS evaluation model to determine
the rate of energy release, cladding oxidation, and hydrogen
generation. Topical Report BAW-10227(P)(A), Revision 1, demonstrated
that the Baker-Just model is conservative in the evaluated post-LOCA
scenarios with respect to the use of the M5 advanced alloy as a fuel
rod cladding material.
Based on the above, the underlying purpose of 10 CFR 50.46 and 10
CFR part 50, Appendix K is still met and literal compliance is not
necessary for use of M5 fuel rod cladding. Therefore, the special
circumstances required by 10 CFR 50.12 for the granting of an exemption
from 10 CFR 50.46 and Appendix K of 10 CFR part 50 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 the licensee an exemption from
the requirements of 10 CFR 50.46 and Appendix K of 10 CFR part 50.
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 (October 26, 2011; 76 FR 6633). This
exemption is effective upon issuance.
Dated at Rockville, Maryland this 31st day of October 2011.
For the Nuclear Regulatory Commission.
Michele G. Evans,
Director, Division of Operating Reactor Licensing, Office of Nuclear
Reactor Regulation.
[FR Doc. 2011-28610 Filed 11-3-11; 8:45 am]
BILLING CODE 7590-01-P
