View source for L-PI-09-125, License Amendment Request and Exemption Request to Support the Use of Optimized Zirlotm Fuel Rod Cladding

{{Adams
| number = ML093280883
| issue date = 11/24/2009
| title = License Amendment Request and Exemption Request to Support the Use of Optimized Zirlotm Fuel Rod Cladding
| author name = Schimmel M
| author affiliation = Northern States Power Co, Xcel Energy
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000282, 05000306
| license number = DPR-042, DPR-060
| contact person = 
| case reference number = L-PI-09-125
| document type = Letter type:L, License-Application for Facility Operating License (Amend/Renewal) DKT 50, Technical Specification, Amendment
| page count = 27
| project = 
| stage = Request
}}

=Text=
{{#Wiki_filter:L-PI-09-125 November 24, 2009                                                  10 CFR 50.90 10 CFR 50.12 U S Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant Units 1 and 2 Dockets 50-282 and 50-306 License Nos. DPR-42 and DPR-60 License Amendment Request and Exemption Request to Support the Use of Optimized ZIRLOTM Fuel Rod Cladding Pursuant to 10 CFR 50.90, Northern States Power Company, a Minnesota corporation (NSPM), doing business as Xcel Energy, hereby requests the following amendment for the Prairie Island Nuclear Generating Plant (PINGP)
Technical Specifications (TS). The Enclosure 1 proposes changes to TS 4.2.1 and TS 5.6.5. These changes are consistent with the Nuclear Regulatory Commission (NRC) allowed use of Optimized ZIRLO' fuel cladding material in Westinghouse and Combustion Engineering Original Equipment Manufacturer (OEM) reactors as issued in Addendum 1-A to Topical Report WCAP-12610-P-A and CENPD-404-P-A, entitled Optimized ZIRLO'.
To support the change and pursuant to 10 CFR 50.12, NSPM is also requesting an exemption from certain requirements of 10 CFR 50.46, Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors, and 10 CFR Part 50, Appendix K, ECCS Evaluation Models for the PINGP.
The exemption request relates solely to the specific types of cladding material described in these regulations for use in light water reactors. The exemption request is included as Enclosure 2.
NSPM requests approval of the proposed amendment and exemption within one calendar year of the submittal date to support the first Optimized ZIRLOTM fuel loading tentatively scheduled for the spring 2011, Unit 1 refueling outage. Upon NRC approval, NSPM requests 60 days to implement the associated changes.
In accordance with 10 CFR 50.91, a copy of this application, with enclosures, is being provided to the designated Minnesota State Official.
1717 Wakonade Drive East
* Welch, Minnesota 55089-9642 Telephone: 651.388.1121

Document Control Desk Page 2 Summary of Commitments This letter contains new commitments listed below:
Commitment                                     Due Date
: 1. In the course of the core reload process approved       Continuous, until the for use at PINGP, and prior to first loading of             contingency requirements Optimized ZIRLOTM,Westinghouse will be                      of the conditions and programmatically required to evaluate the effects of        limitations have been Optimized ZIRLOTMon PINGP core performance and              satisfied.
accident analysis. To satisf NRC Safety Evaluation (SE) for Optimized ZIRLOT{ NSPM will confirm that core reload safety evaluations satisfy conditions and limitations 3, 4, 5, 8, and 10 of the NRC SE for Optimized Z I R L O ~ ~ .
: 2. To satisfy NRC SE for Optimized Z I R L O ~ NSPM
                                                    ~,         Continuous, until the LTA will confirm that Westinghouse provides additional          data up through the fuel confirmatory data associated with Lead Test Assembly        burnup limit applicable for (LTA) programs at other facilities prior to operation       PlNGP has been provided with Optimized Z I R L O ~fuel
                                ~ rod cladding. This           to the NRC.
commitment relates to conditions and limitations 6 and 7 of the NRC SE for Optimized Z I R L O ~ ~ .
If you should have any questions regarding this submittal, please contact Glenn Adams at (6 12) 330-6777.
I declare under penalty of perjury that the foregoing is true and correct.
Executed on November 24,2009 Mark A. Schimmel Site Vice President, Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota

==Enclosures:==

I Evaluation of the Proposed Change
: 2. Request for Exemption from the Provisions of 10 CFR 50.46 and 10 CFR 50 Appendix K to Allow Use of Optimized Z I R L O ~   in~Core Reload Applications cc:      Administrator, Region Ill, USNRC Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC State of Minnesota

ENCLOSURE I Evaluation of the Proposed Change

==Subject:==
License Amendment Request to Revise TS 4.2.1, "Fuel Assemblies" and TS 5.6.5, "Core Operating Limits Report (COLR)" to Support the Use of Optimized ZIRLO" Fuel Rod Cladding I.O   

==SUMMARY==
DESCRIPTION 2.0    DETAILED DESCRIPTION

==2.1    PROPOSED CHANGE==
S

==2.2   BACKGROUND==

==3.0   TECHNICAL EVALUATION==

==4.0    REGULATORY EVALUATION==

4.1    APPLICABLE REGULATORY REQUIREMENTSICRITERIA 4.2    PRECEDENT 4.3    SIGNIFICANT HAZARDS CONSIDERATION

==4.4    CONCLUSION==
S

==5.0   ENVIRONMENTAL CONSIDERATION==

==6.0   REFERENCES==

ATTACHMENTS:
: 1. Technical Specification Pages (Markup)
: 2. Technical Specification Pages (Retyped)
Page 1 of 13

Enclosure I                                                                         NSPM Optimized ZIRLOTM I.O     

==SUMMARY==
DESCRIPTION This license amendment request (LAR) would amend Operating Licenses DPR-42 and DPR-60 for Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2.
Northern States Power Company, a Minnesota corporation (NSPM) requests Nuclear Regulatory Commission (NRC) review and approval of proposed revisions to Technical Specification (TS) Section 4.2.1, Fuel Assemblies, and TS Section 5.6.5, Core Operating Limits Report (COLR). The proposed change will revise the TS to allow the use of Optimized ZIRLOTMfuel rod cladding material.
2.0      DETAILED DESCRIPTION

==2.1      PROPOSED CHANGE==
S Brief descriptions of the associated proposed TS changes are provided below along with discussions of the justification for each change. The specific wording changes to the TS are provided in Attachments 1 and 2 to this enclosure.
TS 4.2.1, "Fuel Assemblies" This LAR proposes to revise TS 4.2.1 by adding Optimized ZIRLOTMas an acceptable fuel rod cladding material.
TS 5.6.5, "Core Operating Limits Report (COLR)"
This LAR proposes to revise TS 5.6.5 to add WCAP-12610-P-A and Addendum I-A to Topical Report WCAP-12610-P-A and CENPD-404-P-A, entitled "Optimized ZIRLOTM"to the list of documents previously reviewed and approved by the NRC.
There are no TS Bases changes associated with this LAR.
In summary, these changes are acceptable because they meet the regulatory criteria for appropriate content of the Technical Specifications. Also, these changes meet the conditions and limitations of NRC Safety Evaluation for Optimized ZIRLOTM(Reference
: 2) as described in the Technical Evaluation.

==2.2     BACKGROUND==

As the nuclear industry pursues longer operating cycles with increased fuel discharge burnup and fuel duty, the corrosion performance requirements for the nuclear fuel cladding become more demanding. Optimized ZIRLOTMwas developed to meet these needs and provides a reduced corrosion rate while maintaining the benefits of mechanical strength and resistance to accelerated corrosion from abnormal chemistry conditions. In addition, fuel rod internal pressures (resulting from the increased fuel Page 2 of 13

Enclosure 1                                                                          NSPM Optimized ZIRLOTM duty, use of integral fuel burnable absorbers, and corrosionltemperature feedback effects) have become more limiting with respect to fuel rod design criteria. Reducing the associated corrosion buildup and thus minimizing temperature feedback effects provides additional margin to the fuel rod internal pressure design criterion.
As prescribed by TS 4.2.1, fuel cladding materials approved for use at the PINGP are Zircaloy or ZIRLOTM. Optimized ZIRLOTMfuel cladding is different from standard ZIRLOTMin two respects: I ) the tin content is lower; and 2) the microstructure is different. This difference in tin content and microstructure can lead to differences in some material properties and the industry has committed to provide irradiated data and validate fuel performance models ahead of burnups achieved in batch application.
Optimized ZIRLOTMis described in Westinghouse topical report WCAP-12610-P-A and CENPD-404-P-A, Addendum l - A entitled "Optimized ZIRLOTM",July 2006 (Reference 1). The staffs safety evaluation for Optimized ZIRLOTMdated June 10,2005 (Reference 2) requires licensees invoking Addendum I-A (for the purpose of implementing Optimized ZIRLOTM)to comply with the ten conditions and limitations listed within the safety evaluation. These conditions and limitations are addressed in Section 3.0 of this LAR.

==3.0     TECHNICAL EVALUATION==

PlNGP is a two unit plant located on the right bank of the Mississippi River, approximately 6 miles northwest of the city of Red Wing, Minnesota. The facility is owned and operated by NSPM. Each unit at the PlNGP employs a two-loop pressurized water reactor designed and supplied by Westinghouse Electric Corporation.
The initial PlNGP application for a Construction Permit and Operating License was submitted to the Atomic Energy Commission (AEC) in April 1967. The Final Safety Analysis Report (FSAR) was submitted for application of an Operating License in January 1971. Unit 1 began commercial operation in December 1973, and Unit 2 began commercial operation in December 4 974.
The PlNGP was designed and constructed to comply with NSPM1sunderstanding of the intent of the AEC General Design Criteria (GDC) for Nuclear Power Plant Construction Permits, as proposed on July 10, 1967. PlNGP was not licensed to NUREG-0800, "Standard Review Plan (SRP).
Westinghouse Electric Company, LLC (Westinghouse) topical report WCAP-12610-P-A and CENPD-404-P-A, Addendum l-A, "Optimized ZIRLOTM",provides the details and results of material testing of Optimized ZIRLOTMcompared to standard ZIRLOTMas well as the material properties to be used in various models and methodologies when analyzing Optimized ZIRLOTM.
The NRC Safety Evaluation (SE) for the topical report (Reference 2) contains ten conditions and limitations. The non-proprietary version of those conditions and Page 3 of 13

Enclosure 1                                                                            NSPM Optimized ZIRLOTM limitations is listed below, copied verbatim from the SE without proprietary information.
Following each condition and limitation is the NSPM response to explain compliance:
: 1.      Until rulemaking to 10 CFR Part 50 addressing Optimized ZIRLOTMhas been completed, implementation of Optimized ZIRLOTMfuel clad requires an exemption from 10 CFR 50.46and 10 CFR Part 50 Appendix K.
Response: The request for exemption from 10 CFR 50.46 and 10 CFR Part 50, Appendix K is included as Enclosure 2 of this LAR.
: 2.      The fuel rod burnup limit for this approval remains at currently established limits:
62 GWd/MTU for Westinghouse fuel designs and 60 GWd/MTU for CE fuel designs.
Response: For any fuel using Optimized ZIRLOTMfuel cladding, the maximum fuel rod burnup limit for Westinghouse fuel designs will continue to be 62 GWd/MTU until such time that a new fuel rod burnup limit is approved for use.
: 3.      The maximum fuel rod waterside corrosion, as predicted by the best-estimate model, will [proprietary limits included in topical report and proprietary version of safety evaluation] of hydrides for all locations of the fuel rod.
Response: The maximum fuel rod waterside corrosion for the fuel product using Optimized ZIRLOTMfuel cladding will be confirmed to be less than the proprietary limits included in the topical report and the proprietary version of safety evaluation of hydrides for all locations of the fuel rod. Confirmation of these modified limits for Optimized ZIRLOTMfuel cladding is required as part of the core reload process.
: 4.      All the conditions listed in previous NRC SE approvals for methodologies used for standard ZIRLOTMand Zircaloy-4 fuel analysis will continue to be met, except that the use of Optimized ZIRLOTMcladding in addition to standard ZIRLOTMand Zircaloy-4 cladding is now approved.
Response: The fuel analysis of Optimized ZIRLOTMfuel cladding will continue to meet the conditions associated with approved methods. For the PINGP, this is a current requirement and confirmation of these conditions is required as part of the core reload process.
: 5. All methodologies will be used only within the range for which ZIRLOTMand Optimized ZIRLOTMdata were acceptable and for which the verifications discussed in Addendum I and responses to RAls were performed.
Response: The application of ZIRLOTMand Optimized ZIRLOTMin approved methodologies will be made consistent with the approach accepted in WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A "Optimized ZIRLOTM",July 2006.
Page 4 of 13 NSPM Optimized ZIRLOTM For the PINGP, this is a current requirement and confirmation of these conditions is required as part of the core reload process.
: 6. The licensee is required to ensure that Westinghouse has fulfilled the following commitment: Westinghouse shall provide the NRC staff with a letter(s) containing the following information (based on the schedule described in response to RAI #3):
: a. Optimized ZIRLOTML TA data from Byron, Calvert Cliffs, Catawba, and Millstone.
: i. Visual ii. Oxidation of fuel rods iii. Profilometry iv. Fuel rod length
: v. Fuel assembly length
: b. Using the standard and Optimized ZIRLOTMdatabase including the most recent LTA data, confirm applicability with currently approved fuel performance models (e-g., measured vs. predicted).
Confirmation of the approved models' applicability up through the projected end of cycle burnup for the Optimized ZIRLOTMfuel rods must be completed prior to their initial batch loading and prior to the startup of subsequent cycles. For example, prior to the first batch application of Optimized ZIRLOTM,sufficient LTA data may only be available to confirm the models' applicability up through 45 GWd/MTU. In this example, the licensee would need to confirm the models up through the end of the initial cycle. Subsequently, the licensee would need to confirm the models based upon the latest LTA data, prior to re-inserting the Optimized ZIRLOTMfuel rods in future cycles. Based upon the LTA schedule, it is expected that this issue may only be applicable to the first few batch implementations since sufficient LTA data up through the burnup limit should be available within a few years.
Response: Westinghouse has provided the NRC with information related to test data and models in the following letters:
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk), SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTM",LTR-NRC-07-1, January 4,2007 (ADAMS Accession No. ML070100389, Proprietary, Not Publicly Available)
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk), SER Compliance with WCAP-126 10-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTMJ1,      LTR-NRC-07-58, November 6,2007 (ADAMS Accession No. ML073130562, Proprietary, Not Publiciy Available)
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk), SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTM",LTR-NRC-07-58 Rev. 1, February 5, 2008 (ADAMS Accession No. ML080390452)
Letter from J. A. Gresham (Westinghouse) to U.S. Nuclear Regulatory Commission, SER Compliance of WCAP-12610-P-A & CENPD-404-P-A Addendum 1-A "Optimized ZIRLO TM",LTR-NRC-08-60, December 30,2008 Page 5 of 13                                       T

Enclosure I                                                                           NSPM Optimized ZIRLOTM Lead Test Assembly (LTA) measured data and favorable results from visual examinations of once and twice-burned LTAs confirm, for at least two cycles of operation, that the current fuel performance models are applicable for Optimized ZIRLOTMfuel rods. Westinghouse will continue to provide additional data from the Optimized ZIRLOTMLTA programs to the NRC after new data for higher burnup/fluence become available. NSPM will confirm that Westinghouse transmits the requisite data such that, as higher burnups / fluences are achieved for Optimized ZIRLOTMclad fuel rods, the requirements of this condition will be met as it applies to the PINGP.
: 7. The licensee is required to ensure that Westinghouse has fulfilled the following commitment: Westinghouse shall provide the NRC staff with a letter containing the following information (based on the schedule described in response to RAI #II):
: a. Vogtle growth and creep data summary reports.
: b. Using the standard ZIRLOTMand Optimized ZIRLOTMdatabase including the most recent Vogtle data, confirm applicability with currently approved fuel performance models (e.g., level of conservatism in W rod pressure analysis, measured vs. predicted, predicted minus measured vs. tensile and compressive stress).
Confirmation of the approved models' applicability up through the projected end of cycle burnup for the Optimized ZlRL 0 TM fuel rods must be completed prior to their initial batch loading and prior to the startup of subsequent cycles. For example, prior to the first batch application of Optimized ZIRLOTM,sufficient LTA data may only be available to confirm the models' applicability up through 45 GWd/MTU. In this example, the licensee would need to confirm the models up through the end of the initial cycle. Subsequently, the licensee would need to confirm the models based upon the latest LTA data, prior to re-inserting the Optimized ZIRLOTMfuel rods in future cycles. Based upon the LTA schedule, it is expected that this issue may only be applicable to the first few batch implementations since sufficient LTA data up through the burnup limit should be available within a few years.
Response: Westinghouse has provided the NRC with information related to test data and models in the following letters:
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk), SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTM",LTR-NRC-07-1, January 4,2007 (ADAMS Accession No. ML070100389, Proprietary, Not Publicly Available)
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk), SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTM",LTR-NRC-07-58, November 6,2007 (ADAMS Accession No. ML073130562, Proprietary, Not Publicly Available)
Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control 9999Desk), SER Compliance with WCAP-12610-P-A and CENPD-404-P-A,

Enclosure 1                                                                           NSPM Optimized ZIRLOTM Addendum I-A, "Optimized ZIRLOTM",LTR-NRC-07-58 Rev. 1, February 5, 2008 (ADAMS Accession No. ML080390452)
Letter from J. A. Gresham (Westinghouse) to U.S. Nuclear Regulatory Commission, SER Compliance of WCAP-12610-P-A & CENPD-404-P-A Addendum 1-A "Optimized ZIRLOTM",LTR-NRC-08-60, December 30,2008 Currently, the data from two cycles of operation has been evaluated and the fuel rod creep models from fuel rod design codes have been used to predict the growth and creep performance of the samples. This information was provided to the NRC in the most recent informational letter (LTR-NRC-08-60) at the end of calendar year 2008. NSPM will confirm that Westinghouse transmits the requisite data such that, as higher burnups 1 fluences are achieved for Optimized ZIRLOTMclad fuel rods, the requirements of this condition will be met as it applies to PINGP.
: 8. The licensee shall account for the relative differences in unirradiated strength (YS and UTS) between Optimized ZIRLOTMand standard ZIRLOTMin cladding and structural analyses until irradiated data for Optimized ZIRLOTMhave been collected and provided to the NRC staff.
: a. For the Westinghouse fuel design analyses:
: i. The measured, unirradiated Optimized ZIRLOTMstrengths shall be used for BOL analyses.
ii. Between BOL up to a radiation fluence of 3.0 x lo2' n/cm2 (E > IMeV),
pseudo-irradiated Optimized ZIRLOTMstrength set equal to linear interpolation between the following two strength level points: At zero fluence, strength of Optimized ZIRLOTMequal to measured strength of Optimized ZIRLOTMand at a fluence of 3.0 x lo2' n/cm2 (E > IMeV),
irradiated strength of standard ZIRLOTMat the fluence of 3.0 x lo2', n/cm2 (E > 1 M e g minus 3 ksi.
iii. During subsequent irradiation from 3.0 x I02' n/cm2 up to 12 x I0'' n/cm2, the differences in strength (the difference at a fluence of 3 x lo2' n/cm2 due to tin content) shall be decreased linearly such that the pseudo-irradiated Optimized ZIRLOTMstrengths will saturate at the same properties as standard ZIRLOTMat 12 x lo2' n/cm2.
: b. For the CE fuel design analyses, the measured, unirradiated Optimized ZIRLOTMstrengths shall be used for all fluence levels (consistent with previously approved methods).
Response: PINGP is a Westinghouse fuel design; therefore, 8.b does not apply.
The fuel analysis of Optimized ZIRLOTMclad fuel rods will use the yield strength and ultimate tensile strength as modified per Conditions 8.a.i, 8.a.ii, and 8.a.iii until such time that irradiated data for Optimized ZIRLOTMstrengths have been collected and provided to the NRC. NSPM will confirm that as higher burnupslfluences are achieved for Optimized ZIRLOTMclad fuel rods, the requirements of this condition will be met as they apply to PINGP.
Page 7 of 13

Enclosure 1                                                                            NSPM Optimized ZIRLOTM
: 9. As discussed in response to RAI #21, forplants introducing Optimized ZIRLOTM that are licensed with LOCBART or STRIKIN-I1 and have a limiting PCT that occurs during blowdo wn or early reflood, the limiting LOCBART or STRIKIN-I1 calculation will be rerun using the specified Optimized ZIRLOTMmaterial properfies. Although not a condition of approval, the NRC staff strongly recommends that, for future evaluations, Westinghouse update all computer models with Optimized ZIRLOTMspecific material properties.
Response: PlNGP is not licensed with LOCBART or STRIKIN-II; therefore, this condition and limitation do not apply.
: 10. Due to the absence of high temperature oxidation data for Optimized ZIRLOTM,the Westinghouse coolability limit on PCT during the locked rotor event shall be
[proprietary limits included in topical report and proprietary version of safety evaluation].
Response: As part of the core reload safety evaluation process, the Westinghouse limit on Peak Cladding Temperature (PCT) during the locked rotor event will be assessed relative to the proprietary limits included in topical report and proprietary version of safety evaluation.

==4.0      REGULATORY EVALUATION==

4.1     Applicable Regulatory Requirements 1 Criteria Title 10 Code of Federal Regulations 50.36, "Technical Specifications":
(c) Technical specifications will include items in the following categories:
(4) Design features. Design features to be included are those features of the facility such as materials of construction and geometric arrangements, which, if altered or modified, would have a significant effect on safety and are not covered in categories described in paragraphs (c) ( I ) , (2), and (3) of this section.
The proposed change to Technical Specifications (TS) 4.2.1 adds Optimized ZIRLOTM to the list of approved fuel rod materials described as design features. As an incremental addition to an existing list in TS 4.2.1, the proposed change is consistent with current content and satisfies the regulatory criteria established for 10 CFR 50.36 for content of the Technical Specifications. Also, the addition of trademark notation "TM" is an editorial change that protects the intellectual property rights of Westinghouse without affecting the Technical Specification content requirements of 10 CFR 50.36.
(5) Administrative controls. Administrative controls are the provisions relating to organization and management, procedures, recordkeeping, review and audit, Page 8 of 13

Enclosure 1                                                                          NSPM Optimized ZIRLOTM and reporting necessary to assure operation of the facility in a safe manner. Each licensee shall submit any reports to the Commission pursuant to approved technical specifications as specified in &sect; 50.4.
The proposed change to TS 5.6.5 adds two analyses to the existing list of analyses approved for use in developing the core operating limits. As an incremental addition to an existing list in TS 5.6.5, the proposed change is consistent with current content and satisfies the regulatory criteria established for 10 CFR 50.36 for content of the Technical Specifications.
Thus, with the changes proposed in this license amendment request, the requirements of 10 CFR 50.36 continue to be met.
General Design Criteria:
The construction of the PlNGP was significantly complete prior to issuance of 10 CFR 50, Appendix A, General Design Criteria (GDC). The PlNGP was designed and constructed to comply with the AEC GDC as proposed on July 10, 1967 as described in the plant Updated Safety Analysis Report (USAR). Furthermore, the PlNGP is committed to selected Appendix A GDC. The PlNGP GDC applicable to fuel cladding integrity is the following:
Criterion 6 - Reactor Core Design. The reactor core shall be designed to function throughout its design lifetime, without exceeding acceptable fuel damage limits which have been stipulated and justified. The core design, together with reliable process and decay heat removal systems, shall provide for this capability under all expected conditions of normal operation with appropriate margins for uncertainties and for transient situations which can be anticipated, including the effects of the loss of power to recirculation pumps, tripping out of a turbine generator set, isolation of the reactor from its primary heat sink, and loss of all offsite power.
PlNGP implementation of the approved reload safety evaluation process provides ongoing assurance that reactor core design meets PlNGP GDC 6, including any fuel design changes. With particular respect to the fuel changes proposed herein, NSPM will confirm that the core design involving Optimized ZIRLOTMwill address the effects of that fuel including the conditions and limitations prescribed by the NRC Safety Evaluation SE for Optimized Z I R L O ~ ~Thus,. the proposed change does not affect conformance with any General Design Criterion differently than described in the PlNGP USAR.
10 CFR 50.46, "Acceptance Criteria For Emergency Core Cooling Systems For Light Water Nuclear Power ReactorsJ':
The proposed change has been evaluated to validate that the subject regulation and requirements continue to be met. NSPM concurs with the NRC SE that an exemption from 10 CFR 50.46, and 10 CFR 50, Appendix K, "ECCS Evaluation Models" is Page 9 of 13

Enclosure 1                                                                       NSPM Optimized ZIRLOTM required. The request for exemption has been provided as Enclosure 2 and provides the basis and justification for relief from these regulations.
4.2     Precedent The NRC has previously approved the use of Optimized Z I R L O ~fuel  ~ cladding material in Combustion Engineering reactors. In a license amendment request dated April 24, 2007 (ADAMS Accession No. ML071220267), Entergy Operations, Inc. proposed to use the Optimized Z I R L O ~   ~ cladding material for Arkansas Nuclear One, Unit 2. The fuel license amendment request herein is similar to the Entergy submittal in that it comparably addresses the conditions and limitations of the applicable NRC SE. The only notable differences relate to the differences in reactor design (Combustion Engineering vs. Westinghouse), which are addressed appropriately in the Technical Evaluation for the PINGP as they apply to the Westinghouse reactor design. The NRC reviewed and approved the license amendment request for Entergy in a Safety Evaluation dated March 26,2008 (ADAMS Accession No. ML080370014).
Also, in a license amendment request dated April 24,2007 (ADAMS Accession No. ML071160348), Entergy Operations, Inc. proposed to use the Optimized Z ~ R L O     fuel~ ~
cladding material for Waterford, Unit 3. The license amendment request herein is similar to the Entergy submittal in that it comparably addresses the conditions and limitations of the applicable NRC SE. The only notable differences relate to the differences in reactor design (Combustion Engineering vs. Westinghouse), which are addressed appropriately in the Technical Evaluation for the PINGP as they apply to the Westinghouse reactor design. The NRC reviewed and approved the license amendment request for Entergy in a Safety Evaluation dated April 16, 2008 (ADAMS Accession No. ML080380004).
4.3     No Significant Hazards Consideration The proposed Technical Specification (TS) change adds Optimized ZIRLOTMto the list of cladding materials approved for use at Prairie Island Nuclear Generating Plant (PINGP). Technical Specifications describe fuel rod material specifically as "Zircaloy or ZIRLO". The proposed change will add Optimized ZIRLOTMto the approved fuel rod cladding materials and will add reference to the supporting NRC-approved analyses, which are WCAP-12610-P-A, VANTAGE+ Fuel Assembly Reference Core Report, April 1995 (Westinghouse Proprietary) and WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTMJ',         July 2006 (Westinghouse Proprietary).
Northern States Power - Minnesota (NSPM) has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:
Page 10 of 13

Enclosure 1                                                                            NSPM Optimized ZIRLOTM I. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No.
Westinghouse Electric Company, LLC (Westinghouse) topical report WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A "Optimized ZIRLOTM",July 2006, provides the details and results of material testing of Optimized ZIRLOTMcompared to standard ZIRLOTMas well as the material properties to be used in various models and methodologies when analyzing Optimized ZIRLOTM.
The Nuclear Regulatory Commission (NRC) has allowed use of Optimized ZIRLOTM fuel cladding material in Westinghouse fueled reactors provided that licensees ensure compliance with the conditions and limitations set forth in the NRC Safety Evaluation (SE) for the topical report. By satisfying the conditions and limitations of the NRC SE through completed actions and its approved reload safety evaluation process, the licensee ensures that the effects of Optimized ZIRLOTMon PINGP core performance are evaluated and that the probability or consequences of previously-evaluated accidents are not increased.
Therefore, the proposed change of adding a cladding material does not result in an increase to the probability or consequences of an accident previously evaluated.
: 2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No.
Material properties of this fuel design have been evaluated in Westinghouse topical report WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A "Optimized ZIRLOTM",July 2006. That report provides the details and results of material testing of Optimized ZIRLOTMcompared to standard ZIRLOTMas well as the material properties to be used in various models and methodologies when analyzing Optimized ZIRLOTM. Neither that topical report nor the associated NRC SE identifies the possibility of a new or different kind of accident resulting from this change for generic application in Westinghouse reactors. As demonstrated in that topical report and stated in the NRC SE, there is reasonable assurance that under both normal and accident conditions, the Optimized ZIRLOTMfuel cladding will be able to safely operate and comply with NRC regulations. By satisfying the conditions and limitations of the NRC SE by virtue of its completed actions and its approved reload safety evaluation process, the licensee ensures that the effects of Optimized ZIRLOTMare evaluated and will not create the possibility of a new or different kind of accident. Assurance that the possibility of new or different type of accidents will not be created on a site-specific basis is inherent to the reload safety evaluation process approved for use at the PINGP. Site specific evaluation of the

Enclosure 1                                                                            NSPM Optimized ZIRLOTM PlNGP core designs with Optimized ZIRLOTMwill be performed programmatically and necessarily by the approved reload safety evaluation process.
Therefore, the proposed change of adding a cladding material does not create the possibility of a new or different kind of accident from any accident previously evaluated.
: 3. Does the proposed change involve a significant reduction in a margin of safety?
Response: No.
The cladding material used in the fuel rods is designed and tested to prevent excessive fuel temperatures, excessive internal rod gas pressure due to fission gas releases, and excessive cladding stresses and strains. Optimized ZIRLOTMwas developed to meet these needs and provides a reduced corrosion rate while maintaining the benefits of mechanical strength and resistance to accelerated corrosion from abnormal chemistry conditions. Westinghouse topical report WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A "Optimized ZIRLOTMJ1,              July 2006, provides the details and results of material testing of Optimized ZIRLOTMcompared to standard ZIRLOTMas well as the material properties to be used in various models and methodologies when analyzing Optimized ZIRLOTM.The NRC has allowed use of Optimized ZIRLOTMfuel cladding material detailed within this topical report as detailed within their SE. Therefore, the change in material does not result in a significant reduction in a margin of safety.
Based on the above, NSPM concludes that the proposed amendments present no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.
4.4       Conclusions In conclusion, based on the considerations discussed above, ( I ) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

==5.0      ENVIRONMENTAL CONSIDERATION==

The proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(~)(9).Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.
Page 12 of 13

Enclosure 1                                                                 NSPM Optimized ZIRLOTM

==6.0     REFERENCES==
: 1. WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTM",July 2006 (ADAMS Accession No. ML062080576, Proprietary, Not Publicly Available)
: 2. Letter from H. N. Berkow (USNRC) to J. A. Gresham (Westinghouse), Final Safety Evaluation for Addendum to Topical Report WCAP-12610-P-A and CENPD-404-P-A, "Optimized ZIRLOTM",June 10,2005 (ADAMS Accession No. ML051670395, Proprietary, Not Publicly Available)
: 3. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTM",LTR-NRC-07-1, January 4, 2007 (ADAMS Accession No. ML070100389, Proprietary, Not Publicly Available)
: 4. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLO   TMJ1, LTR-NRC-07-58, November 6,2007 (ADAMS Accession No. ML073130562, Proprietary, Not Publicly Available)
: 5. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTM",LTR-NRC-07-58 Rev. I,February 5,2008 (ADAMS Accession No. ML080390452)
: 6. Letter from J. A. Gresham (Westinghouse) to U.S. Nuclear Regulatory Commission, SER Compliance of WCAP-I 2610-P-A & CENPD-404-P-A Addendum 1-A "Optimized ZIRLOTM",LTR-NRC-08-60, December 30, 2008 Page 13 of 13

ATTACHMENT I to ENCLOSURE 1 Technical Specification Pages (Markup) 2 pages follow

Tkc sitc for the Pmide Island Nucbar Generatitkg Phnt is located an thc w s t b n k of thc Mi~issippiRivix, approxima&ly6 miles nox~wcstof the city af R& FVing, Minnc~tw.Thc silc sxciiusiox~arm b o m d a ~bas a minimum rdius of 7 1S rnctcrs frt'lamthe e ~ t l k lri ~ xof either r w ~ b r ,
The rcad'ifr sIxak3 cot18                 asset~hblim,Each ~lsscnnbIyrzhalk coa~sist of a sxlatrix af ZIrcaloy                 fuel reds wit11 so initial con~pmitionof uetbld or sligl~tfycnl.ietm& urar~imdit~xi&(U02) %sfuel tx~eiteri~d.
Limitcd substitutioas of zirconium alby or stainfcsssteel. filler rods hr fuel rads, In accor&nm w id1 appotped spplicatiat'~s          of &el m d canfipfi%tiorzs, rx3iBy be uscd. FBEol ass@~~bIics      shall bc limited to those he1 d o s i g ~that
                                                                                                   ~
heivc brccn analyzed with app2kabbe N R t st&T appravcd codes and tn~&ods and sh~wraby Q s t s an: a d y s c s -to cat11ply with all fbtircl safety desigr~bases.
rZ. f il11itcc8 sumbcr af lead tcht assembfies 'Ef38thave r ~ & cconzplctcd reprosc stati%~c     tcstlng rmy bc pEaad in noaiinrieng core regions.
4 . 2 2 Cattraf Rod d%ssea~bEics Rairie XsSnnd                                                           Uzlrit I - ArurelKfmcnt No*iSi-Units 1. and 2                                      4,O-%               Unit 2 -- An~crdmcntNo, 4-W
: 18. WCAP-7908-A, " ' F A C m - A FORTRAN IV Cade fox T h a ~ ~Traasi~~rts ul        in n U02Fud RoP;
: 19. !V@AF990J-F& "LOFTEM Code EkscriptianY';
3.I;C32P-10965-P-A, "AN@:A i76est~11gIirc1useAdva11ced Nodal Computer"Code";
: 22. T%?@AP-11394-P-&,     "&fetlxdalog~rfar the A11aIysrs of the Dropped R d Evefit";
: 23. $%'CAP-11596-P-A, .'Qtiahffi~atimof the P H Q m - P , ' A N C Design System for Resstzrized IYeter hixctar Cores";
N\~cIec~ff
: 24. 5XgCA4P-179I Q Rev. 1-A, "R~ss'e'uizexSafe@Valve Set Pressure shift"7:
: 26. TV@AU-148$2-P-a%      "'mTW-02. Mo&hm~gcmdQamlificstion fix 7,tres~t1&w%PI.rssikpize.c%Water Reactor Nozir-LWA Safety k~alyses";am+
2 7. \\'CAP- 1GtlO9-P-A,'Xealisbs Large B r e d LOCA EvaIanha~~
h4etl1ocblou Using Az1to111ated         a1 Treattne~~tof
                      ~ncertaintyketllod
               .I
: 28. WCAP-12610-P-A, "VANTAGE+ Fuel Assembly Reference Core Report"; and
: 29. WCAP-12610-P-A & CENPD-404-P-A, Addendum 1-A, "Optimized Z I R L O ~ ~ " .
I Unit I - ,kne~lhe-r1tNO.4~23446WS)-
5.0-36   Unit 2 - Afp1e1ilhaxt No. 4223 44HB-

ATTACHMENT 2 to ENCLOSURE 1 Technical Specification Pages (Retyped) 3 pages follow

!-hesite for the Prairi+?  Island Nuclcar Gmwating Plant is lwated on the \vest ba3k ufr h M~ i s i ~ i p p Rvgr, i      ~ p p x i n t a b l y6 mihg na&kvma af as:city of 81d. Wiag, hfinhamata, 'llw si& ealmim                 burrdd~.y. kas fx minimum mdia3 sf71 5 metem fram the mnter !in@of eithgr The maetsr ~ I L L L mntai~121, keE wgmbllies, Emh wsmbBy $hall wasis%
ofs ma&ix of jl'jlcaloy. ZIIILO*~,or O p h i e r d Z I R L ORrel a@in[tid w m m i t l ~ of' n wimafr or ~!i&tlya r k ~ k ~rmium  d
                                                                                ~ rods kifh dimid. (UQ3) 1 fuel m~t&dl, Limiled s u b & i o f n i m ~ i u mzsltoy m slsi~l.~ss                 s&el
                     ~ ke8 mds, ia wwrmce with *roved 8~tissli;ans filler m d foal"                                                                   af @el rod cmfiwratiw~~,       may b~              Fuel w m h l i e s shJ1 be l i r n i ~ dso $ha=
fud 3 $ i p g &at:h b ~ bwnc an&~lyxed         with &ppliabJb;tm   C gtaff~&~ppm~*&
cad= B& r n ~ & ~ & md &@%#*a          by        or d y w $ ta "ply         with dli h e !
               &sip h ~ s A. limii~edtrumkr @fjit?d#@I 8~mhlit~                     &&tbmte wortplg&4rep~smtuhuet e g w may k plaxd id fiadimibing e                       m~ a h n s .

 ]I B, a;iYCAB-7908*A5'TFAGTMN - A E 6 x ta~U02Fuel Rod";
nemm! T r a ~ ~ i min 28, WC~419-128 18-Pa-A, "VA3TPabaEe Fuel Asgcaxbiy bfg,m%:c: Core Rwaax";and Unit I  ACWB   %';rbNo. W W
                         %,6-36 1Jnlk 2 -- Agaendm~atNO, W W

28.WCM- H 26 H 0-P-A md CENP wOptimigdXIRlvO      m..
: a. RC S p$e%%u~   a ~ %tempmture d            1i m i far
                                             ~ heat-up, @sddo%v~,        Law
   .femp@mtuK               c"~$l~aEj@,.
x;zmmtia6t'~,           md hyko~tat
   &mingy  P63RV IiR a ~ l ~ r a &and
                                   % Srpfety Iajiec~im Trnpemr~      ao~well a8 bmmp md coa1dcbm              $hail 'trsr: m&blisb~d aad r l i 3 ria the PTLR fag the f@ll~wig%g:
IaC9-l34.3, ""RGSmenwe and Iha~pramre(Px"1')Limiitg";
               ""RCSLmps MODE 4":
I,CU 3.4.f~~
LC0 3,4.."$ *";RCS  L a o p MODE 5, L LC0 3,4,1%,TKFW      TC         WE O V C ~ T ~ S BProtmtion UXC          (r lFQ;BP)-
                 &aesar C~olmtS ~ B PGaM       ~ E Leg T c ~ ~ ~ p r n a ~ r n (RC311;1;ldT)3 NPety Ifde~tio~    ($1) Pump Diwble T~rn~m$lorc**,
LC0 J,4,13, ""L3w T c m ~ m t O~ vew r c ~ ~ t rPt w e c t i a a (LTQP)
M e t o r C m l m i Sys&m CQZ~    Lgg T ~ r r a p a t u c CRCSCL*T)5 %fay I ~ j ~ a ($1)    i m Pump Diwble T&~npemtm";md LC0 3,5;&4," X C S S$ut'sw~i'%i".
5-0-37      Unit '2- Amm&t~tntNo-
* Unit 1 - m m k r n t Nils. 442 448

Enclosure 2                                                                           NSPM Optimized ZIRLOTM ENCLOSURE 2 Request for Exemption from the Provisions of 10 CFR 50.46 and 10 CFR Part 50, Appendix K to Allow Use of Optimized ZIRLOTMin Core Reload Applications Purpose In accordance with 10 CFR 50.12, "Specific Exemptions," NSPM requests an exemption from the provisions of 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors," and 10 CFR 50, Appendix K, "ECCS Evaluation Models" to allow the use of Optimized Z I R L O ~fuel  ~ rod cladding in future core reload applications for Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2. The regulation in 10 CFR 50.46 contains acceptance criteria for the emergency core cooling system (ECCS) for reactors that have fuel rods fabricated either with Zircaloy or ZIRLOTM. 10 CFR Part 50, Appendix K paragraph I.A.5, requires the Baker-Just equation to be used to predict the rates of energy release, hydrogen concentration, and cladding oxidation for the metal-water reaction. The Baker-Just equation assumed the use of a zirconium alloy different than Optimized ZIRLOTM.Therefore, an exemption to 10 CFR 50.46 and 10 CFR Part 50, Appendix K is required to support the use of Optimized ZIRLOTMfuel rod cladding. The exemption request relates solely to the specific cladding material specified in these regulations (i.e., fuel rods clad with Zircaloy or ZIRLOTM). This request will provide for the application of the acceptance criteria of 10 CFR 50.46, and 10 CFR 50, Appendix K to fuel assembly designs utilizing Optimized ZIRLOTMfuel cladding.

===Background===
As the nuclear industry pursues longer operating cycles with increased fuel discharge burnup and fuel duty, the corrosion performance requirements for the nuclear fuel cladding become more demanding. Optimized ZIRLOTMwas developed to meet these needs and provides a reduced corrosion rate while maintaining the benefits of mechanical strength and resistance to accelerated corrosion from abnormal chemistry conditions. In addition, fuel rod internal pressures (resulting from the increased fuel duty, use of integral fuel burnable absorbers, and corrosion/temperature feedback effects) have become more limiting with respect to fuel rod design criteria. Reducing the associated corrosion buildup and thus minimizing temperature feedback effects, provides additional margin to the fuel rod internal pressure design criterion.
Starting in spring 201 1, the reloads for Prairie lslland Units 1 and 2 will contain fuel rods clad with Optimized ZIRLOTM.
Technical Specification (TS) changes for Prairie Island Units 1 and 2 are required to allow the use of Optimized ZIRLOTMfuel rod cladding for core reload applications. The Page 1 of 5

Enclosure 2                                                                         NSPM Optimized ZIRLOTM request for these changes is provided in the License Amendment Request enclosed herein.
Technical Justification of Acceptability Westinghouse Electric Company, LLC (Westinghouse) topical report WCAP-I 2610-P-A
  & CENPD-404-P-A, Addendum I-A, "Optimized ZIRLO TM"(Reference I ) , provides the details and results of material testing of Optimized ZIRLOTMcompared to standard ZIRLOTMas well as the material properties to be used in various models and methodologies when analyzing Optimized ZIRLOTM.The NRC Safety Evaluation (SE)
(Reference 2) for the topical report contains ten conditions and limitations. The first condition requires an exemption from 10 CFR 50.46 and 10 CFR 50, Appendix K (which is being requested herein). Westinghouse has provided the NRC with information related to test data and models (References 3, 4, 5 and 6) to address conditions and limitations 6 and 7. Condition and limitation 9 does not apply because Prairie Island Units 1 and 2 are not licensed with LOCBART or STRIKIN-II. The remaining conditions and limitations are addressed in the PlNGP Units 1 and 2 license amendment request and the evaluations required to support core reload activities.
The reload safety evaluations will ensure that acceptance criteria are met for insertion of assemblies with fuel rods clad with Optimized ZIRLOTMunder 10 CFR 50.59 requirements. These assemblies will be evaluated using NRC approved methods and models of the reload safety evaluation process to address the use of Optimized ZI RLOTM.
Justification of Exemption 10 CFR 50.12, "Specific exemptions," states that the NRC may grant exemptions from the requirements of the regulations of this part provided three conditions are met. The three conditions are: I ) the exemption is authorized by law; 2) the exemption will not present an undue risk to the health and safety of the public; and 3) the exemption is consistent with the common defense and security.
The requested exemption to allow the use of Optimized ZIRLOTMfuel rod cladding material rather than Zircaloy or ZIRLOTMfor core reload applications at the PlNGP Units 1 and 2, satisfies these criteria as described below.
: 1. This exemption is authorized by law As required by 10 CFR 50.12 (a)(l), this requested exemption is "authorized by law."
The selection of a specified cladding material in 10 CFR 50.46, and implied in 10 CFR Part 50, Appendix K, was adopted at the discretion of the Commission consistent with its statutory authority. No statute required the NRC to adopt this specification. Additionally, the NRC has the authority under Section 50.12 to grant exemptions from the requirements of Part 50 upon showing proper justification.
Further, it should be noted that, by submitting this exemption request, NSPM does Page 2 of 5

Enclosure 2                                                                           NSPM Optimized ZIRLOTM not seek an exemption from the acceptance and analytical criteria of 10 CFR 50.46, and 10 CFR Part 50, Appendix K. The intent of the request is solely to allow the use of criteria set forth in these regulations for application to the Optimized ZIRLOTMfuel rod cladding material.
: 2. This exemption will not present an undue risk to public health and safetv The reload safety evaluations will ensure that acceptance criteria are met for the insertion of assemblies with fuel rods clad with Optimized ZIRLOTM.Fuel assemblies using Optimized ZIRLOTMfuel rod cladding will be evaluated using NRC approved analytical methods and plant specific models to address the changes in the cladding material properties. The safety analysis for PINGP Units 1 and 2 is supported by the applicable site specific TSs. Reload cores are required to be operated in accordance with the operating limits specified in the TSs. Thus, the granting of this exemption request will not pose an undue risk to public health and safety.
: 3. This exemption is consistent with common defense and securitv As noted above, the exemption request is to allow the application of the aforementioned regulations to an improved fuel rod cladding material. By satisfying the conditions and limitations of the NRC Safety Evaluation (SE) (Reference 2) for the topical report, NSPM demonstrates compliance with the applicable regulations as they relate to fuel cladding. Furthermore, NSPM has established commitments to ensure continued compliance once the Optimized ZIRLOTMfuel cladding is received at PINGP. The special nuclear material in these assemblies is required to be handled and controlled in accordance with approved procedures. Use of full regions of Optimized ZIRLOTMfuel rod cladding in the PINGP Units 1 and 2 cores will not affect plant operations and is consistent with common defense and security.
Special circumstances support the issuance of an exemption 10 CFR 50.12(a)(2) states that the NRC will not consider granting an exemption to the regulations unless special circumstances are present. The requested exemption meets the special circumstances of 10 CFR 50.12(a)(2)(ii) which states that, "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." In this particular circumstance, application of the subject regulations is not necessary to achieve the underlying purpose of the rule.
10 CFR 50.46 identifies acceptance criteria for ECCS performance at nuclear power plants. Due to the similarities in the material properties of the Optimized ZIRLOTMand standard ZIRLOTM,the current ECCS analysis approach remains applicable. In the course of the core reload process approved for use at the PINGP, Westinghouse will be programmatically required to evaluate the effects of Optimized ZIRLOTMusing Loss of Page 3 of 5

Enclosure 2                                                                             NSPM Optimized ZIRLOTM Coolant Accident (LOCA) methods approved for the site to ensure that assemblies with Optimized ZIRLOTMfuel rod cladding material meet all LOCA safety criteria.
The intent of 10 CFR Part 50, Appendix K, paragraph I.A.5, is to apply an equation for I   rates of energy release, hydrogen generation, and cladding oxidation from a metal-water reaction that conservatively bounds all post-LOCA scenarios (i.e., the Baker-Just equation). Application of the Baker-Just equation has been demonstrated to be appropriate for the Optimized ZIRLOTMalloy. Due to the similarities in the composition of the Optimized ZIRLOTMand standard ZIRLOTMfuel rod cladding materials, the application of the Baker-Just equation will continue to conservatively bound all post-LOCA scenarios.
Conclusion The acceptance criteria and requirements of 10 CFR 50.46, and 10 CFR 50, Appendix K, currently are limited in applicability to the use of fuel rods clad with Zircaloy or ZIRLOTM. 10 CFR 50.46 and 10 CFR 50, Appendix K, do not apply to the proposed use of Optimized ZIRLOTMfuel rod cladding material since Optimized ZIRLOTMhas a slightly different composition than Zircaloy or ZIRLOTM.With the approval of this exemption, these regulations will be applied to Optimized ZIRLOTM.
In order to support the use of Optimized ZIRLOTMfuel rod cladding material, an exemption from the requirements of 10 CFR 50.46 and 10 CFR Part 50, Appendix K is requested. As required by 10 CFR 50.12, the requested exemption is authorized by law, does not present undue risk to public health and safety, and is consistent with common defense and security. Approval of this exemption request does not violate the underlying purpose of the rule. In addition, special circumstances do exist to justify the approval of an exemption from the subject requirements.
References
: 1. WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTM",July 2006 (ADAMS Accession No. ML062080576, Proprietary, Not Publicly Available)
: 2. Letter from H. N. Berkow (USNRC) to J. A. Gresham (Westinghouse), Final Safety Evaluation for Addendum to Topical Report WCAP-12610-P-A and CENPD-404-P-A, "Optimized ZIRLOTM",June 10,2005 (ADAMS Accession No. ML051670395, Proprietary, Not Publicly Available)
: 3. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum l-A, "Optimized ZIRLOTM1',    LTR-NRC-07-1, January 4,2007 (ADAMS Accession No. ML070100389, Proprietary, Not Publicly Available)
: 4. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum 1-A, "Optimized ZIRLOTM",LTR-NRC-07-58, November 6,2007 (ADAMS Accession No. ML073130562, Proprietary, Not Publicly Available)
Page 4 of 5 NSPM Optimized ZIRLOTM
: 5. Letter from J. A. Gresham (Westinghouse) to USNRC (Document Control Desk),
SER Compliance with WCAP-12610-P-A and CENPD-404-P-A, Addendum I-A, "Optimized ZIRLOTM",LTR-NRC-07-58 Rev. I,February 5,2008 (ADAMS Accession No. ML080390452)
: 6. Letter from J. A. Gresham (Westinghouse) to U.S. Nuclear Regulatory Commission, SER Compliance of WCAP-12610-P-A & CENPD-404-P-A Addendum I - A "Optimized ZIRLOTM",LTR-NRC-08-60, December 30,2008 Page 5 of 5}}