Text

Request to Revise Technical Specifications 2.1.1 for Minimum Critical Power Ratio Safety Limits
	ML17241A278
Person / Time
Site:	LaSalle
Issue date:	08/29/2017
From:	Gullott D; Exelon Generation Co
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML17241A283	List: RS-17-100, Request to Revise Technical Specifications 2.1.1 for Minimum Critical Power Ratio Safety Limits;
References
	RS-17-100
	Download: ML17241A278 (47)
	v • d • e

V.Jinti~:id t~c_)dCi Exelon Generation Offer Proprietary Information -Withhold from Public Disclosure Under 10 CFR 2.390 RS-17-100 10 CFR 50.90 August 29, 2017 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374

Subject:

Request to Revise Technical Specifications 2.1.1 for Minimum Critical Power Ratio Safety Limits - LaSalle County Station, Units 1 and 2 In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Exelon Generation Company, LLC, (EGC) requests a proposed change to modify Technical Specifications (TS} 2.1.1, "Reactor Core SLs [Safety Limits]," for LaSalle County Station (LSCS), Units 1 and 2. Specifically, this change incorporates revised LSCS, Units 1 and 2, minimum critical power ratio safety limits (SLMCPRs) due to the cycle specific analyses performed by Global Nuclear Fuel (GNF) for LSCS Unit 1, Cycle 17, and LSCS Unit 2, Cycle 17.

There are six attachments to this letter. Attachment 1 provides an evaluation of the proposed change. Attachment 2 provides the current TS page with the proposed change indicated for LSCS. Attachment 3 provides GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR for LSCS Unit 1 Cycle 17. Attachment 4 provides GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR for LSCS Unit 2 Cycle 17.

Attachments 3 and 4 contain proprietary information as defined by 10CFR2.390. GNF, as the owner of the proprietary information, has executed the enclosed affidavits, which identify that the enclosed proprietary information has been handled and classified as proprietary, is customarily held in confidence, and has been withheld from public disclosure. The proprietary information was provided to Exelon Nuclear in a GNF transmittal that is referenced by the affidavit. The proprietary information has been faithfully reproduced in the enclosed document such that the affidavit remains applicable. Accordingly, it is respectfully requested that the enclosed proprietary information be withheld from public disclosure in accordance with 10 CFR 2.390 and 10 CFR 9.17. Attachments 5 and 6 contain non-proprietary versions of Attachments 3 and 4, respectively.

Attachments 3 and 4 contain Proprietary Information. Withhold from Public Disclosure Under 10 CFR 2.390.

When separated from Attachments 3 and 4, this document is decontrolled.

August 29, 2017 U.S. Nuclear Regulatory Commission Page 2 Proprietary Information - Withhold from Public Disclosure Under 10 CFR 2.390 EGG requests approval of the proposed amendment by February 7, 2018. Once approved, the amendment shall be implemented prior to startup from the February 2018 refueling outage (i.e., L 1R17).

In accordance with 1o CFR 50.91, "Notice for public comment; State consultation," paragraph (b),

EGG is notifying the State of Illinois of this application for a change to the TS by transmitting a copy of this letter and its attachments to the designated State Official.

There are no regulatory commitments contained in this letter. Should you have any questions concerning this letter, please contact Ms. Lisa A. Simpson at (630) 657-2815.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 29th day of August 2017.

Respectfully, David M. Gullatt Manager - Licensing Exelon Generation Company, LLC Attachments:

1) Evaluation of Proposed Changes

2) Proposed Technical Specifications Changes - Marked-up TS Page

3) GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 1 Cycle 17 (GNF Proprietary Information)

4) GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 2 Cycle 17 (GNF Proprietary Information)

5) GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 1 Cycle 17 (Non-Proprietary Information)

6) GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 2 Cycle 17 (Non-Proprietary Information) cc: NRG Regional Administrator, Region Ill NRG Senior Resident Inspector, LaSalle County Station Illinois Emergency Management Agency - Division of Nuclear Safety Attachments 3 and 4 contain Proprietary Information. Withhold from Public Disclosure Under 10 CFR 2.390.

When separated from Attachments 3 and 4, this document is decontrolled.

ATTACHMENT 1 Evaluation of Proposed Changes

Subject:

Request to Revise Technical Specification 2.1.1 for Minimum Critical Power Ratio Safety Limits - LaSalle County Station, Units 1 and 2 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedents 4.3 No Significant Hazards Consideration 4.4 Conclusions 5.0 ENVIRONMENTAL CONSIDERATON

6.0 REFERENCES

Page 1 of 6

ATTACHMENT 1 Evaluation of Proposed Changes 1.0

SUMMARY

DESCRIPTION The proposed change would revise Technical Specifications (TS) 2.1.1, "Reactor Core SLs

[Safety Limits], 11 for LaSalle County Station (LSCS), Units 1 and 2. Specifically, the proposed change incorporates revised Safety Limit Minimum Critical Power Ratios (SLMCPRs) due to the cycle specific analyses performed by Global Nuclear Fuel (GNF) for LSCS, Unit 1, Cycle 17, and LSCS, Unit 2, Cycle 17.

The proposed change is described in detail in Section 2.0 of this attachment.

2.0 DETAILED DESCRIPTION For Unit 1:

The proposed amendment reflects a decrease of the two recirculation loop MCPR SL limit from

1.13 to ;

:: 1.11 and a decrease in the single recirculation loop MCPR SL from ;::: 1.15 to ;::: 1.13.

For Unit 2:

The proposed amendment reflects a decrease of the two recirculation loop MCPR SL limit from

1.14 to ;

:: 1.12 and a decrease in the single recirculation loop MCPR SL from ;::: 1.17 to ;::: 1.15.

The proposed changes have been evaluated in accordance with 10 CFR 50.91 (a)(1) using the criteria in 10 CFR 50.92(c), and it has been determined that the change does not involve a significant hazards consideration. The bases for these determinations are included in Section 4.0 of this Attachment. provides the current TS page with the proposed change indicated for LSCS, Units 1 and 2.

3.0 TECHNICAL EVALUATION

The proposed TS change will revise the SLMCPRs contained in TS 2.1.1 for two recirculation loop operation and single recirculation loop operation to reflect the changes in the cycle specific analysis performed by GNF for LSCS, Unit 1, Cycle 17, and Unit 2, Cycle 17.

The proposed SLMCPR values were developed for LSCS, Unit 1, Cycle 17, and Unit 2, Cycle 17, and will be confirmed in the future on a cycle-specific basis. The proposed SLMCPR values for LSCS, Units 1 and 2, were developed with GNFs NRG-approved SLMCPR methodology. The new SLMCPRs are calculated using NRG-approved methodology described in NEDE-24011-P-A, "General Electric Standard Application for Reactor Fuel," Revision 22 (Reference 1). A listing of the associated NRG-approved methodologies for calculating the SLMCPRs is provided in Section 3.0 of Attachments 3 and 4, respectively.

The SLMCPR analysis establishes SLMCPR values that will ensure that during normal operation and during abnormal operational transients, at least 99.9% of all fuel rods in the core do not experience transition boiling if the limit is not violated. The SLMCPRs are calculated to include cycle specific parameters and, in general, are dominated by two key parameters:

(1) flatness of the core bundle-by-bundle (MCPR) distribution; and (2) flatness of the bundle pin-by-pin power/A-Factor distribution.

Page 2 of 6

ATTACHMENT 1 Evaluation of Proposed Changes Information supporting the cycle specific SLMCPRs is included in Attachments 3 and 4. Those attachments summarize the methodology, inputs, and results for the change in the SLMCPRs.

No plant hardware or operational changes are required with these proposed changes.

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria The proposed change has been evaluated to determine whether applicable regulations and requirements continue to be met.

10 CFR 50.36, 11 Technical specifications," paragraph (c)(1), requires that power reactor facility TS include safety limits for process variables that protect the integrity of certain physical barriers that guard against the uncontrolled release of radioactivity. The SLMCPR analysis establishes SLMCPR values that will ensure that during normal operation and during abnormal operational transients, at least 99.9% of all fuel rods in the core do not experience transition boiling if the limit is not violated. Thus, the SLMCPR is required to be contained in TS.

General Design Criterion (GDC) 10, "Reactor design, 11 of Appendix A to 10 CFR Part 50 states,

'The reactor core and associated coolant, control, and protection systems shall be designed with appropriate margin to assure that specified acceptable fuel design limits are not exceeded during any condition of normal operation, including the effects of anticipated operational occu rrences. 11 Guidance on the acceptability of the reactivity control systems, the reactor core, and fuel system design is provided in NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants." Standard Review Plan (SRP), Section 4.2, "Fuel System Design," of NUREG-0800 (Reference 2), specifies all fuel damage criteria for evaluation of whether fuel designs meet the specified acceptable fuel design limits. SRP, Section 4.4, "Thermal and Hydraulic Design, 11 of NUREG-0800 (Reference 3), states, 11 The limiting (minimum) value of [departure from nucleate boiling ratio] DNBR, [changes in critical heat flux ratio] CHFR, or [critical power ratio] CPR correlations is to be established such that at least 99.9 percent of the fuel rods in the core will not experience a DNB or boiling transition during normal operation or [anticipated operational occurrences] AOOs. 11 4.2 Precedents

1. Letter from V. Sreenivas (U.S. Nuclear Regulatory Commission) to B. C. Hanson, (Exelon Nuclear), "Limerick Generating Station, Unit 2 - Issuance of Amendment Re:

Safety Limit Minimum Critical Power Ratio Change (CAC No. MF8943), 11 dated March 29, 2017 (ADAMS Accession No. ML17024A089)

2. Letter from N. DiFrancesco (U.S. Nuclear Regulatory Commission) to M. J. Pacilio (Exelon Nuclear), "LaSalle County Station, Unit 2 - Issuance of Amendment No. 192 Regarding Technical Specification Change for Safety Limit Minimum Critical Power Ratio (TAC No. ME9769) 11 dated February 27, 2013 (ADAMS Accession No. ML13050A637)

Page 3 of 6

ATIACHMENT1 Evaluation of Proposed Changes

3. Letter from N. DiFrancesco (U.S. Nuclear Regulatory Commission) to M. J. Pacilio (Exelon Nuclear), "LaSalle County Station, Unit 1 - Issuance of Amendment Regarding Technical Change for Safety Limit Minimum Critical Power Ratio (TAC No. ME7331)"

dated March 1, 2012 (ADAMS Accession No. ML120520606) 4.3 No Significant Hazards Consideration In accordance with 10 CFR 50.90, 11 Application for amendment of license, construction permit, or early site permit, 11 Exelon Generation Company, LLC, (EGC) is requesting a change to the Technical Specifications (TS) of Facility Operating License Nos. NPF-11 and NPF-18 for LaSalle County Station (LSCS), Units 1 and 2.

According to 10 CFR 50.92, "Issuance of amendment," paragraph (c), a proposed amendment to an operating license involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not:

(1) Involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) Involve a significant reduction in a margin of safety.

In support of this determination, an evaluation of each of the three criteria set forth in 10 CFR 50.92 is provided below:

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

The Safety Limit Minimum Critical Power Ratio (SLMCPR) is defined as the lowest ratio of that power which results in the onset of transition boiling to the actual bundle power at the same location. The Global Nuclear Fuel (GNF) methodology is applied for each reload to assure that more than 99.9% of the fuel rods in the core are expected to avoid boiling transition for the most severe abnormal operational transient described in LaSalle UFSAR Chapter 15.0. The new SLMCPRs preserve the existing margin to transition boiling. The SLMCPR satisfies the requirements of General Design Criterion 10 of Appendix A to 10 CFR 50 regarding acceptable fuel design limits.

The MCPR safety limit is re-evaluated for each reload using NRG-approved methodologies.

The analyses for LSCS, Unit 1, Cycle 17, have concluded that a two recirculation loop SLMCPR of;::: 1.11, based on the application of GNF's NRG-approved SLMCPR methodology, will ensure that this acceptance criterion is met. For single recirculation loop operation, a SLMCPR of;::: 1.13 also ensures that this acceptance criterion is met. The MCPR operating limits are presented and controlled in accordance with the LSCS, Unit 1 Core Operating Limits Report (COLA).

Page 4 of 6

ATTACHMENT 1 Evaluation of Proposed Changes Similarly, the analyses for LSCS, Unit 2, Cycle 17, have concluded that a two recirculation loop SLMCPR of ~ 1.12, based on the application of GNF's NRG-approved SLMCPR methodology, will ensure that this acceptance criterion is met. For single recirculation loop operation, a SLMCPR of ~ 1.15 also ensures that this acceptance criterion is met. The MCPR operating limits are presented and controlled in accordance with the LSCS, Unit 2 Core Operating Limits Report (COLR).

The requested TS changes do not involve any plant modifications or operational changes that could affect system reliability or performance or that could affect the probability of operator error. The requested changes do not affect any postulated accident precursors, do not affect any accident mitigating systems, and do not introduce any new accident initiation mechanisms. Therefore, the proposed TS changes do not involve a significant increase in the probability or consequences of any 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.

The SLMCPR is a TS numerical value, calculated to ensure that during normal operating and during abnormal operational transients, at least 99.9% of all fuel rods in the core do not experience transition boiling if the limit is not violated. The new SLMCPRs are calculated using NRG-approved methodology discussed in NEDE-24011-P-A, 11 General Electric Standard Application for Reactor Fuel, 11 Revision 22. The proposed changes do not involve any new modes of operation, any changes to setpoints, or any plant modifications. The proposed revised MCPR safety limits have been shown to be acceptable for Unit 1 Cycle 17 and Unit 2 Cycle 17 operation and will be confirmed in the future on a cycle-specific basis.

The core operating limits will continue to be developed using NRG-approved methods. The proposed MCPR safety limits or methods for establishing the core operating limits do not result in the creation of any new precursors to an accident. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

There is no reduction in the margin of safety previously approved by the NRC as a result of the proposed change to the SLMCPRs. The new SLMCPRs are calculated using methodology discussed in NEDE-24011-P-A, 11 General Electric Standard Application for Reactor Fuel, 11 Revision 22. The SLMCPRs ensure that during normal operation and during abnormal operational transients, at least 99.9% of all fuel rods in the core do not experience transition boiling if the limit is not violated, thereby preserving the fuel cladding integrity. The proposed TS changes do not involve a significant reduction in the margin of safety previously approved by the NRC.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Page 5 of 6

ATTACHMENT 1 Evaluation of Proposed Changes Based on the above, EGG concludes that the proposed amendments do not involve a 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, (1) 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

A review has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a 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(c)(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.

6.0 REFERENCES

1. NEDE-24011-P-A, "General Electric Standard Application for Reactor Fuel, 11 Revision 22, November 2015 (ADAMS Accession No. ML15324A145) 11

2. U.S. Nuclear Regulatory Commission Standard Review Plan (SRP) 4.2, Fuel System Design, 11 Revision 3, (ADAMS Accession No. ML070740002) of NUREG-0800, 11 Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition - Reactor, 11 March 2007

3. U.S. Nuclear Regulatory Commission Standard Review Plan (SRP) 4.4, "Thermal and Hydraulic Design, 11 Revision 2, (ADAMS Accession No. ML070550060) of NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition - Reactor, 11 March 2007 Page 6 of 6

ATTACHMENT 2 LASALLE COUNTY STATION UNIT2 Docket No. 50-374 License No. NPF-18 Request for Technical Specification Change for Minimum Critical Power Ratio Safety Limits Proposed Technical Specifications Changes MARKED-UP TS PAGE 2.0-1

SLs 2.0 2.0 SAFETY LIMITS CSLs) 2 .1 SLs 2 .1.1 Reactor Core SLs 2.1.1.1 With the reactor steam dome pressure < 700 psi a or core fl ow < 10% rated core flow:

THERMAL POWER shall be ~ 25% RTP.

2.1.1.2 With the reactor steam dome pressure ~ 700 psi a and core flow~ 10% rated core flow:

For Unit 1, MCPR shall be~~ for two recirculation loop operation or~~ for single recirculation loop operation.

For Unit 2, MCPR shall be~~ for two recirculation loop operation or~~ for single recirculation loop operation.

2.1.1.3 Reactor vessel water level shall be greater than the top of active irradiated fuel.

2.1.2 Reactor Coolant System Pressure SL Reactor steam dome pressure shall be~ 1325 psig.

2.2 SL Violations With any SL violation, the following actions shall be completed within 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />s:

2.2.1 Restore compliance with all SLs; and 2.2.2 Insert all insertable control rods.

LaSalle 1 and 2 2.0 1 Amendment No. 220/206

Proprietary Information - Withhold from Public Disclosure Under 10 CFR 2.390 ATTACHMENT 3 LASALLE COUNTY STATION UNIT 1 Docket No. 50-373 License No. NPF-11 Request for Technical Specification Change for Minimum Critical Power Ratio Safety Limits GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 1 Cycle 17 (GNF Proprietary Information)

Attachments 3 and 4 contain Proprietary Information. Withhold from Public Disclosure Under 10 CFR 2.390.

When separated from Attachments 3 and 4, this document is decontrolled.

Proprietary Information - Withhold from Public Disclosure Under 10 CFR 2.390 ATTACHMENT 4 LASALLE COUNTY STATION UNIT2 Docket No. 50-37 4 License No. NPF-18 Request for Technical Specification Change for Minimum Critical Power Ratio Safety Limits GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 2 Cycle 17 (GNF Proprietary Information)

Attachments 3 and 4 contain Proprietary Information. Withhold from Public Disclosure Under 10 CFR 2.390.

When separated from Attachments 3 and 4, this document is decontrolled.

ATTACHMENT 5 LASALLE COUNTY STATION UNIT 1 Docket No. 50-373 License No. NPF-11 Request for Technical Specification Change for Minimum Critical Power Ratio Safety Limits GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 1 Cycle 17 (Non-Proprietary Information)

May 2017 004N2838 R1-NP PLM Specification 004N2838 Revision 1 Non-Proprietary Information - Class I (Public)

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Information Notice This is a non-proprietary version of the document 004N2838-R1-P, which has the proprietary information removed. Portions of the document that have been removed are indicated by an open and closed bracket as shown here (( )).

Important Notice Regarding Contents of this Report Please Read Carefully The design, engineering, and other information contained in this document is furnished for the purpose of providing information regarding the requested changes to the Technical Specification SLMCPR for Exelon Corporation LaSalle Unit 1. The only undertakings of GNF-A with respect to information in this document are contained in the contract between GNF-A and Exelon Corporation, and nothing contained in this document shall be construed as changing that contract. The use of this information by anyone other than Exelon Corporation, or for purposes other than those for which it is intended is not authorized; and with respect to any unauthorized use, GNF-A makes no representation or warranty, and assumes no liability as to the completeness, accuracy, or usefulness of the information contained in this document.

Information Notice Page 2 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Table of Contents 1.0 Summary .............................................................................................................................. 4 2.0 Regulatory Basis.................................................................................................................. 4 3.0 Methodology ........................................................................................................................ 4 3.1. Methodology Restrictions ................................................................................................. 5 4.0 Discussion............................................................................................................................. 6 4.1. Major Contributors to SLMCPR Change .......................................................................... 6 4.2. Deviations from Standard Uncertainties............................................................................ 6 4.2.1. R-Factor ...................................................................................................................... 7 4.2.2. Core Flow Rate and Random Effective TIP Reading ................................................. 7 4.2.3. Flow Area Uncertainty ................................................................................................ 7 4.2.4. Fuel Axial Power Shape Penalty................................................................................. 7 5.0 References ............................................................................................................................ 9 List of Tables Table 1. Monte Carlo SLMCPR .................................................................................................. 11 Table 2. Description of Core ........................................................................................................ 12 Table 3. Deviations from Standard Uncertainties ........................................................................ 13 Table of Contents Page 3 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public) 1.0 Summary The requested changes to the Technical Specification (TS) Safety Limit Minimum Critical Power Ratio (SLMCPR) values are 1.11 for Two Loop Operation (TLO) and 1.13 for Single Loop Operation (SLO) for LaSalle Unit 1 Cycle 17. Additional details are provided in Table 1.

The primary reason for the change is LaSalle Unit 1 changing to the reduced power distribution uncertainty methodology, which inherently lowers the SLMCPR. The previous SLMCPR TS was based upon higher uncertainties.

2.0 Regulatory Basis Title 10 of the Code of Federal Regulations (10 CFR) 50.36, Technical Specifications, Paragraph (c)(1), requires that power reactor facility TS include safety limits for process variables that protect the integrity of certain physical barriers that guard against the uncontrolled release of radioactivity. The fuel cladding is one of the physical barriers that separate the radioactive materials from the environment. The purpose of the SLMCPR is to ensure that Specified Acceptable Fuel Design Limits (SAFDLs) are not exceeded during steady state operation and analyzed transients.

General Design Criterion (GDC) 10, Reactor Design, of Appendix A to 10 CFR Part 50, General Design Criteria for Nuclear Power Plants, states that the reactor core and associated coolant, control, and protection systems shall be designed with appropriate margin to assure that the SAFDLs are not exceeded during any condition of normal operation, including the effects of anticipated operational occurrences.

Guidance on the acceptability of the reactivity control systems, the reactor core, and fuel system design is provided in NUREG-0800, Standard Review Plan [SRP] for the Review of Safety Analysis Reports for Nuclear Power Plants. Specifically, SRP, Section 4.2, Fuel System Design, specifies all fuel damage criteria for evaluation of whether fuel designs meet the SAFDLs. SRP Section 4.4, Thermal Hydraulic Design, provides guidance on the review of thermal-hydraulic design in meeting the requirement of GDC 10 and the fuel design criteria established in SRP Section 4.2.

3.0 Methodology GNF performs SLMCPR calculations in accordance with NEDE-24011-P-A General Electric Standard Application for Reactor Fuel, (GESTAR II) (Reference 1) for plants such as LaSalle Unit 1 that are equipped with the GNF 3DMonicore core monitoring system, by using the following Nuclear Regulatory Commission (NRC) approved methodologies and uncertainties:

NEDC-32601P-A, Methodology and Uncertainties for Safety Limit MCPR Evaluations, August 1999. (Reference 2)

Summary Page 4 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

NEDC-32694P-A, Power Distribution Uncertainties for Safety Limit MCPR Evaluations, August 1999. (Reference 3)

NEDC-32505P-A, R-Factor Calculation Method for GE11, GE12 and GE13 Fuel, Revision 1, July 1999. (Reference 4)

These methodologies were used for the LaSalle Unit 1 Cycle 16 and the Cycle 17 SLMCPR calculations.

3.1. Methodology Restrictions Four restrictions were identified on page 3 of NRCs Safety Evaluation (SE) relating to the General Electric (GE) Licensing Topical Reports (LTRs) NEDC-32601P, NEDC-32694P, and in Amendment 25 to NEDE-24011-P-A (Reference 5).

The following statement was extracted from the generic compliance report for the GNF2 fuel assembly design (Reference 6) that GNF sent to the NRC in March of 2007:

The NRC Safety Evaluation (SE) for NEDC-32694P-A provides four actions to follow whenever a new fuel design is introduced. These four conditions are listed in Section 3 of the SE. In the last paragraph of Section 3.2.2 of the Technical Evaluation Report included in the SE are the statements GE has evaluated this effect for the 8x8, 9x9, and 10x10 lattices and has indicated that the R-Factor uncertainty will be increased to account for the correlation of rod power uncertainties and it is noted that the effect of the rod-to-rod correlation has a significant dependence on the fuel lattice (e.g., 9x9 versus 10x10).

Therefore, in order to insure the adequacy of the R-Factor uncertainty, the effect of the correlation of rod power calculation uncertainties should be reevaluated when the NEDC-32601P methodology is applied to a new fuel lattice.

Therefore, the definition of a new fuel design is based on the lattice array dimensions (e.g., NxN). Because GNF2 is a 10x10, and the evaluations in NEDC-32694P-A include 10x10, then these four actions are not applicable to GNF2.

In an NRC audit report (Reference 7) for this document, Section 3.4.1 page 59 states:

The NRC staffs SE of NEDC-32694P-A (Reference 19 of NEDC-33270P) provides four actions to follow whenever a new fuel design is introduced. These four conditions are listed in Section 3.0 of the SE. The analysis and evaluation of the GNF2 fuel design was evaluated in accordance with the limitations and conditions stated in the NRC staffs SE, and is acceptable.

Methodology Page 5 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Another methodology restriction is identified on page 4 of the NRCs SE relating to the GE LTR NEDC-32505P (Reference 8). Specifically, it states that if new fuel is introduced, GENE must confirm that the revised R-factor method is still valid based on new test data. NEDC-32505P addressed the GE12 10x10 lattice design (i.e., how the R-Factor for a rod is calculated based upon its immediate surroundings (fuel rods, water rods or channel wall)). Validation is provided by the fact that the methodology generates accurate predictions of Critical Power Ratio (CPR) with reasonable bias and uncertainty. The applicability of the R-Factor method is coupled and documented (along with fuel specific additive constants) with the GEXL correlation development (Reference 9), which is submitted as a part of GESTAR II compliance for each new fuel product line.

4.0 Discussion In this discussion, the TLO nomenclature is used for two recirculation loops in operation, and the SLO nomenclature is used for one recirculation loop in operation.

Table 2 provides the description of the current cycle and previous cycle for the reference loading pattern as defined by NEDE-24011-P-A (Reference 1).

4.1. Major Contributors to SLMCPR Change In general, for a given power-flow state point, the calculated safety limit is dominated by two key parameters: (1) flatness of the core bundle-by-bundle Minimum Critical Power Ratio (MCPR) distribution, and (2) flatness of the bundle pin-by-pin power/R-Factor distribution.

Greater flatness in either parameter yields more rods susceptible to boiling transition and thus a higher calculated SLMCPR. Therefore, the calculated SLMCPR may change whenever there are changes to the core configuration or to the fresh fuel designs. The plant-cycle specific SLMCPR methodology accounts for these factors.

The bundle designs and core loadings have been consistent since the GNF2 new fuel introduction in Cycle 15. The current SLMCPR TS values, which were established in Cycle 15, were based upon an older methodology. The newer reduced power distribution uncertainty methodology (References 2 and 3), which inherently results in a lower SLMCPR, was applied in Cycle 16 and Cycle 17. This plant has exhibited similar SLMCPR results over the past two cycles with this newer methodology (Table 1).

4.2. Deviations from Standard Uncertainties Table 3 provides a list of deviations from NRC-approved uncertainties (References 2 and 3). A discussion of deviations from these NRC-approved values follows, all of which are conservative relative to NRC-approved values.

Discussion Page 6 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public) 4.2.1. R-Factor GNF has generically increased the GEXL R-Factor uncertainty from (( )) to account for an increase in channel bow due to the phenomena called control blade shadow corrosion-induced channel bow, which is not accounted for in the channel bow uncertainty component of the approved R-Factor uncertainty. Reference 10 technically justifies that a GEXL R-Factor uncertainty of (( )) accounts for a channel bow uncertainty of up to

(( )). The LaSalle Unit 1 Cycle 17 analysis shows an expected channel bow uncertainty of (( )), which is bounded by a GEXL R-Factor uncertainty of (( )). Thus, the use of a GEXL R-Factor uncertainty of (( )) adequately accounts for the expected control blade shadow corrosion-induced channel bow. The effect of this change is considered not significant (i.e., < 0.005 increase on SLMCPR).

4.2.2. Core Flow Rate and Random Effective TIP Reading In Reference 11 GNF committed to the expansion of the state points used in the determination of the SLMCPR. Consistent with the Reference 11 commitments, GNF performs analyses at the rated core power and minimum licensed core flow point in addition to analyses at the rated core power and rated core flow point. The approved SLMCPR methodology is applied at each state point that is analyzed.

For the TLO calculations performed at 82.8% core flow, the approved uncertainty values for the core flow rate (2.5%) and the random effective Traversing In-Core Probe (TIP) reading (1.2%)

are conservatively adjusted by dividing them by 82.8/100.

The core flow and random TIP reading uncertainties used in the SLO minimum core flow SLMCPR analysis remain the same as in the rated core flow SLO SLMCPR analysis because these uncertainties (which are substantially larger than used in the TLO analysis) already account for the effects of operating at reduced core flow.

4.2.3. Flow Area Uncertainty GNF has calculated the flow area uncertainty for GNF2 using the process described in Section 2.7 of Reference 2. It was determined that the flow area uncertainty for GNF2 is conservatively bounded by a value of (( )). Because this is larger than the Reference 2 value of (( )) the bounding value was used in the SLMCPR calculations. The effect of this change is considered not significant (i.e., < 0.005 increase on SLMCPR).

4.2.4. Fuel Axial Power Shape Penalty The GEXL correlation critical power uncertainty and bias are established for each fuel product line according to a process described in NEDE-24011-P-A (Reference 1).

Discussion Page 7 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

GNF determined that higher uncertainties and non-conservative biases in the GEXL correlations for certain types of axial power shapes could exist relative to the NRC-approved methodology values (References 12, 13, and 14). GNF2 product lines are potentially affected in this manner only by Double-Hump (D-H) axial power shapes.

The D-H axial shape did not occur on any of the limiting bundles (i.e., those contributing to the 0.1% rods susceptible to transition boiling) in the current and/or prior cycle limiting cases.

Therefore, D-H power shape penalties were not applied to the GEXL critical power uncertainty or bias.

Discussion Page 8 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public) 5.0 References

1. Global Nuclear Fuel, General Electric Standard Application for Reactor Fuel, NEDE-24011-P-A, Revision 22, November 2015.

2. GE Nuclear Energy, Methodology and Uncertainties for Safety Limit MCPR Evaluations, NEDC-32601P-A, August 1999.

3. GE Nuclear Energy, Power Distribution Uncertainties for Safety Limit MCPR Evaluations, NEDC-32694P-A, August 1999.

4. GE Nuclear Energy, R-Factor Calculation Method for GE11, GE12 and GE13 Fuel, NEDC-32505P-A Revision 1, July 1999.

5. Letter, Frank Akstulewicz (NRC) to Glen A. Watford (GNF-A) Acceptance for Referencing of Licensing Topical Reports NEDC-32601P, Methodology and Uncertainties for Safety Limit MCPR Evaluations; NEDC-32694P, Power Distribution Uncertainties for Safety Limit MCPR Evaluation; and Amendment 25 to NEDE-24011-P-A on Cycle-Specific Safety Limit MCPR (TAC Nos. M97490, M99069 and M97491),

MFN-003-099, March 11, 1999.

6. Letter, Andrew A. Lingenfelter (GNF-A) to NRC Document Control Desk with cc to MC Honcharik (NRC), GNF2 Advantage Generic Compliance with NEDE-24011P-A (GESTAR II), NEDC-33270P, March 2007, and GEXL17 Correlation for GNF2 Fuel, NEDC-33292P, March 2007, FLN-2007-011, March 14, 2007.

7. Memorandum, Michelle C. Honcharik (NRC) to Stacy L. Rosenberg (NRC), Audit Report for Global Nuclear Fuels GNF2 Advantage Fuel Assembly Design GESTAR II Compliance Audit, September 25, 2008, (ADAMS Accession Number ML081630579).

8. Letter, Thomas H. Essig (NRC) to Glen A. Watford (GNF-A), Acceptance for Referencing of Licensing Topical Report NEDC-32505P, Revision 1, R-factor Calculation Method for GE11, GE12 and GE13 Fuel, (TAC Nos. M99070 and M95081), MFN-046-98, January 11, 1999.

9. Global Nuclear Fuel, GEXL17 Correlation for GNF2 Fuel, NEDC-33292P, Revision 3, April 2009.

10. Letter, John F. Schardt (GNF-A) to NRC Document Control Desk with attention to Mel B. Fields (NRC), Shadow Corrosion Effects on SLMCPR Channel Bow Uncertainty, FLN-2004-030, November 10, 2004.

11. Letter, Jason S. Post (GENE) to NRC Document Control Desk with attention to Chief, Information Management Branch, et al. (NRC), Part 21 Final Report: Non-Conservative SLMCPR, MFN 04-108, September 29, 2004.

References Page 9 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

12. Letter, Glen A. Watford (GNF-A) to NRC Document Control Desk with attention to Joseph E. Donoghue (NRC), Final Presentation Material for GEXL Presentation -

February 11, 2002, FLN-2002-004, February 12, 2002.

13. Letter, Glen A. Watford (GNF-A) to NRC Document Control Desk with attention to Alan Wang (NRC), NRC Technology Update - Proprietary Slides - July 31 - August 1, 2002, FLN-2002-015, October 31, 2002.

14. Letter, Jens G. Munthe Andersen (GNF-A) to NRC Document Control Desk with attention to Alan Wang (NRC), GEXL Correlation for 10X10 Fuel, FLN-2003-005, May 31, 2003.

References Page 10 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Table 1. Monte Carlo SLMCPR Previous Cycle Current Cycle Limiting Cases Limiting Cases Rated Power Rated Power Rated Power Rated Power Rated Description Minimum Core Flow Rated Core Flow Minimum Core Flow Core Flow Limiting Cycle Exposure Point Beginning of Cycle (BOC) /

EOC EOC MOC MOC/EOC Middle of Cycle (MOC) /

End of Cycle (EOC)

Cycle Exposure at Limiting Point 14050 14050 7500 7500/14000 (MWd/STU)

((

))

Requested Change to the TS SLMCPR N/A1 1.11 (TLO) / 1.13 (SLO)

Note:

1. The TS SLMCPR for the previous cycle (Cycle 16) is based on the Cycle 15 TS SLMCPR (1.13 (TLO) / 1.15 (SLO)).

Table 1. Monte Carlo SLMCPR Page 11 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Table 2. Description of Core Description Previous Cycle Current Cycle Core Rated Power (MWt) 3546 3546 Minimum Flow at Rated Power 82.8% 82.8%

(% rated core flow)

Number of Bundles in the Core 764 764 Batch Sizes and Types:

(Number of Bundles in the Core)

Fresh Fresh: 288 GNF2 Fresh: 276 GNF2 Once-Burnt Once-Burnt: 296 GNF2 Once-Burnt: 288 GNF2 Twice-Burnt Twice-Burnt: 180 ATRIUM10 Twice-Burnt: 200 GNF2 Thrice-Burnt or more Fresh Fuel Batch Average Enrichment 4.03 4.04 (Weight%)

Core Monitoring System 3DMonicore 3DMonicore Table 2. Description of Core Page 12 of 13

004N2838 R1-NP Non-Proprietary Information - Class I (Public)

Table 3. Deviations from Standard Uncertainties NRC Approved Value Description Previous Cycle Current Cycle

(%)

Power Distribution Uncertainties GEXL R-Factor (( )) (( )) (( ))

Random Effective TIP Reading All TLO Cases at Rated Power and 1.2 1.45 1.45 Minimum Flow Non-Power Distribution Uncertainties Channel Flow Area Variation (( )) (( )) (( ))

Total Core Flow Measurement All TLO Cases at Rated Power and 2.5 3.02 3.02 Minimum Flow Table 3. Deviations from Standard Uncertainties Page 13 of 13

Global Nuclear Fuel - Americas AFFIDAVIT I, Brian R. Moore, state as follows:

(1) I am the General Manager, Core & Fuel Engineering, Global Nuclear Fuel - Americas, LLC (GNF-A), and have been delegated the function of reviewing the information described in paragraph (2) which is sought to be withheld, and have been authorized to apply for its withholding.

(2) The information sought to be withheld is contained in GNF proprietary report 004N2838 R1-P, GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR LaSalle Unit 1 Cycle 17, dated May 2017. GNF proprietary information in 004N2838 R1-P is identified by a dotted underline placed within double square brackets. ((This sentence is an example.{3})) GNF proprietary information in some tables is identified with double square brackets before and after the object. In each case, the superscript notation {3} refers to Paragraph (3) of this affidavit, which provides the basis for the proprietary determination.

(3) In making this application for withholding of proprietary information of which it is the owner or licensee, GNF-A relies upon the exemption from disclosure set forth in the Freedom of Information Act (FOIA), 5 USC Sec. 552(b)(4), and the Trade Secrets Act, 18 USC Sec. 1905, and NRC regulations 10 CFR 9.17(a)(4), and 2.390(a)(4) for trade secrets (Exemption 4). The material for which exemption from disclosure is here sought also qualify under the narrower definition of trade secret, within the meanings assigned to those terms for purposes of FOIA Exemption 4 in, respectively, Critical Mass Energy Project v.

Nuclear Regulatory Commission, 975 F2d 871 (DC Cir. 1992), and Public Citizen Health Research Group v. FDA, 704 F2d 1280 (DC Cir. 1983).

(4) Some examples of categories of information which fit into the definition of proprietary information are:

a. Information that discloses a process, method, or apparatus, including supporting data and analyses, where prevention of its use by GNF-A's competitors without license from GNF-A constitutes a competitive economic advantage over other companies;

b. Information which, if used by a competitor, would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product;

c. Information which reveals aspects of past, present, or future GNF-A customer-funded development plans and programs, resulting in potential products to GNF-A;

d. Information which discloses patentable subject matter for which it may be desirable to obtain patent protection.

The information sought to be withheld is considered to be proprietary for the reasons set forth in paragraphs (4)a. and (4)b. above.

004N2838 R1-P Affidavit Page 1 of 3

(5) To address 10 CFR 2.390 (b) (4), the information sought to be withheld is being submitted to NRC in confidence. The information is of a sort customarily held in confidence by GNF-A, and is in fact so held. The information sought to be withheld has, to the best of my knowledge and belief, consistently been held in confidence by GNF-A, no public disclosure has been made, and it is not available in public sources. All disclosures to third parties including any required transmittals to NRC, have been made, or must be made, pursuant to regulatory provisions or proprietary agreements which provide for maintenance of the information in confidence. Its initial designation as proprietary information, and the subsequent steps taken to prevent its unauthorized disclosure, are as set forth in paragraphs (6) and (7) following.

(6) Initial approval of proprietary treatment of a document is made by the manager of the originating component, the person most likely to be acquainted with the value and sensitivity of the information in relation to industry knowledge, or subject to the terms under which it was licensed to GNF-A.

(7) The procedure for approval of external release of such a document typically requires review by the staff manager, project manager, principal scientist or other equivalent authority, by the manager of the cognizant marketing function (or his delegate), and by the Legal Operation, for technical content, competitive effect, and determination of the accuracy of the proprietary designation. Disclosures outside GNF-A are limited to regulatory bodies, customers, and potential customers, and their agents, suppliers, and licensees, and others with a legitimate need for the information, and then only in accordance with appropriate regulatory provisions or proprietary agreements.

(8) The information identified in paragraph (2) is classified as proprietary because it contains details of GNF-As fuel design and licensing methodology. The development of this methodology, along with the testing, development and approval was achieved at a significant cost to GNF-A.

The development of the fuel design and licensing methodology along with the interpretation and application of the analytical results is derived from an extensive experience database that constitutes a major GNF-A asset.

(9) Public disclosure of the information sought to be withheld is likely to cause substantial harm to GNF-A's competitive position and foreclose or reduce the availability of profit-making opportunities. The information is part of GNF-A's comprehensive BWR safety and technology base, and its commercial value extends beyond the original development cost.

The value of the technology base goes beyond the extensive physical database and analytical methodology and includes development of the expertise to determine and apply the appropriate evaluation process. In addition, the technology base includes the value derived from providing analyses done with NRC-approved methods.

The research, development, engineering, analytical, and NRC review costs comprise a substantial investment of time and money by GNF-A.

The precise value of the expertise to devise an evaluation process and apply the correct analytical methodology is difficult to quantify, but it clearly is substantial.

004N2838 R1-P Affidavit Page 2 of 3

GNF-A's competitive advantage will be lost if its competitors are able to use the results of the GNF-A experience to normalize or verify their own process or if they are able to claim an equivalent understanding by demonstrating that they can arrive at the same or similar conclusions.

The value of this information to GNF-A would be lost if the information were disclosed to the public. Making such information available to competitors without their having been required to undertake a similar expenditure of resources would unfairly provide competitors with a windfall, and deprive GNF-A of the opportunity to exercise its competitive advantage to seek an adequate return on its large investment in developing and obtaining these very valuable analytical tools.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on this 16th day of May 2017.

Brian R. Moore General Manager, Core & Fuel Engineering Global Nuclear Fuel - Americas, LLC 3901 Castle Hayne Road Wilmington, NC 2840 I Brian.Moore@ge.com 004N2838 Rl-P Affidavit Page 3 of 3

ATTACHMENT 6 LASALLE COUNTY STATION UNIT2 Docket No. 50-37 4 License No. NPF-18 Request for Technical Specification Change for Minimum Critical Power Ratio Safety Limits GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR - LaSalle Unit 2 Cycle 17 (Non-Proprietary Information)

May 2017 004N2839 R1-NP PLM Specification 004N2839 Revision 1 Non-Proprietary Information - Class I (Public)

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Information Notice This is a non-proprietary version of the document 004N2839-R1-P, which has the proprietary information removed. Portions of the document that have been removed are indicated by an open and closed bracket as shown here (( )).

Important Notice Regarding Contents of this Report Please Read Carefully The design, engineering, and other information contained in this document is furnished for the purpose of providing information regarding the requested changes to the Technical Specification SLMCPR for Exelon Corporation LaSalle Unit 2. The only undertakings of GNF-A with respect to information in this document are contained in the contract between GNF-A and Exelon Corporation, and nothing contained in this document shall be construed as changing that contract. The use of this information by anyone other than Exelon Corporation, or for purposes other than those for which it is intended is not authorized; and with respect to any unauthorized use, GNF-A makes no representation or warranty, and assumes no liability as to the completeness, accuracy, or usefulness of the information contained in this document.

Information Notice Page 2 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Table of Contents 1.0 Summary .............................................................................................................................. 4 2.0 Regulatory Basis.................................................................................................................. 4 3.0 Methodology ........................................................................................................................ 4 3.1. Methodology Restrictions ................................................................................................. 5 4.0 Discussion............................................................................................................................. 6 4.1. Major Contributors to SLMCPR Change .......................................................................... 6 4.2. Deviations from Standard Uncertainties............................................................................ 7 4.2.1. R-Factor ...................................................................................................................... 7 4.2.2. Core Flow Rate and Random Effective TIP Reading ................................................. 7 4.2.3. Flow Area Uncertainty ................................................................................................ 7 4.2.4. Fuel Axial Power Shape Penalty................................................................................. 8 5.0 References ............................................................................................................................ 9 List of Tables Table 1. Monte Carlo SLMCPR .................................................................................................. 11 Table 2. Description of Core ........................................................................................................ 12 Table 3. Deviations from Standard Uncertainties ........................................................................ 13 Table of Contents Page 3 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public) 1.0 Summary The requested changes to the Technical Specification (TS) Safety Limit Minimum Critical Power Ratio (SLMCPR) values are 1.12 for Two Loop Operation (TLO) and 1.15 for Single Loop Operation (SLO) for LaSalle Unit 2 Cycle 17. Additional details are provided in Table 1.

The primary reason for the change is LaSalle Unit 2 changing to the reduced power distribution uncertainty methodology, which inherently lowers the SLMCPR. The previous SLMCPR TS was based upon higher uncertainties.

2.0 Regulatory Basis Title 10 of the Code of Federal Regulations (10 CFR) 50.36(c)(1), Technical Specifications, Paragraph (c)(1), requires that power reactor facility TS include safety limits for process variables that protect the integrity of certain physical barriers that guard against the uncontrolled release of radioactivity. The fuel cladding is one of the physical barriers that separate the radioactive materials from the environment. The purpose of the SLMCPR is to ensure that Specified Acceptable Fuel Design Limits (SAFDLs) are not exceeded during steady state operation and analyzed transients.

General Design Criterion (GDC) 10, Reactor Design, of Appendix A to 10 CFR Part 50, General Design Criteria for Nuclear Power Plants, states that the reactor core and associated coolant, control, and protection systems shall be designed with appropriate margin to assure that the SAFDLs are not exceeded during any condition of normal operation, including the effects of anticipated operational occurrences.

Guidance on the acceptability of the reactivity control systems, the reactor core, and fuel system design is provided in NUREG-0800, Standard Review Plan [SRP] for the Review of Safety Analysis Reports for Nuclear Power Plants. Specifically, SRP, Section 4.2, Fuel System Design, specifies all fuel damage criteria for evaluation of whether fuel designs meet the SAFDLs. SRP Section 4.4, Thermal Hydraulic Design, provides guidance on the review of thermal-hydraulic design in meeting the requirement of GDC 10 and the fuel design criteria established in SRP Section 4.2.

3.0 Methodology GNF performs SLMCPR calculations in accordance with NEDE-24011-P-A General Electric Standard Application for Reactor Fuel, (GESTAR II) (Reference 1) for plants such as LaSalle Unit 2 that are equipped with the GNF 3DMonicore core monitoring system, by using the following Nuclear Regulatory Commission (NRC) approved methodologies and uncertainties:

NEDC-32601P-A, Methodology and Uncertainties for Safety Limit MCPR Evaluations, August 1999. (Reference 2)

Summary Page 4 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

NEDC-32694P-A, Power Distribution Uncertainties for Safety Limit MCPR Evaluations, August 1999. (Reference 3)

NEDC-32505P-A, R-Factor Calculation Method for GE11, GE12 and GE13 Fuel, Revision 1, July 1999. (Reference 4)

These methodologies were used for the LaSalle Unit 2 Cycle 16 and the Cycle 17 SLMCPR calculations.

3.1. Methodology Restrictions Four restrictions were identified on page 3 of NRCs Safety Evaluation (SE) relating to the General Electric (GE) Licensing Topical Reports (LTRs) NEDC-32601P, NEDC-32694P, and in Amendment 25 to NEDE-24011-P-A (Reference 5).

The following statement was extracted from the generic compliance report for the GNF2 fuel assembly design (Reference 6) that GNF sent to the NRC in March of 2007:

The NRC Safety Evaluation (SE) for NEDC-32694P-A provides four actions to follow whenever a new fuel design is introduced. These four conditions are listed in Section 3 of the SE. In the last paragraph of Section 3.2.2 of the Technical Evaluation Report included in the SE are the statements GE has evaluated this effect for the 8x8, 9x9, and 10x10 lattices and has indicated that the R-Factor uncertainty will be increased to account for the correlation of rod power uncertainties and it is noted that the effect of the rod-to-rod correlation has a significant dependence on the fuel lattice (e.g., 9x9 versus 10x10).

Therefore, in order to insure the adequacy of the R-Factor uncertainty, the effect of the correlation of rod power calculation uncertainties should be reevaluated when the NEDC-32601P methodology is applied to a new fuel lattice.

Therefore, the definition of a new fuel design is based on the lattice array dimensions (e.g., NxN). Because GNF2 is a 10x10, and the evaluations in NEDC-32694P-A include 10x10, then these four actions are not applicable to GNF2.

In an NRC audit report (Reference 7) for this document, Section 3.4.1 page 59 states:

The NRC staffs SE of NEDC-32694P-A (Reference 19 of NEDC-33270P) provides four actions to follow whenever a new fuel design is introduced. These four conditions are listed in Section 3.0 of the SE. The analysis and evaluation of the GNF2 fuel design was evaluated in accordance with the limitations and conditions stated in the NRC staffs SE, and is acceptable.

Methodology Page 5 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Another methodology restriction is identified on page 4 of the NRCs SE relating to the GE LTR NEDC-32505P (Reference 8). Specifically, it states that if new fuel is introduced, GENE must confirm that the revised R-factor method is still valid based on new test data. NEDC-32505P addressed the GE12 10x10 lattice design (i.e., how the R-Factor for a rod is calculated based upon its immediate surroundings (fuel rods, water rods or channel wall)). Validation is provided by the fact that the methodology generates accurate predictions of Critical Power Ratio (CPR) with reasonable bias and uncertainty. The applicability of the R-Factor method is coupled and documented (along with fuel specific additive constants) with the GEXL correlation development (References 9), which is submitted as a part of GESTAR II compliance for each new fuel product line.

LaSalle Unit 2 Cycle 17 includes GNF3 Lead Use Assemblies (LUAs). These bundles have been located such that the SLMCPR calculation predicts that they have no rods in transition boiling when the core is at the SLMCPR. These LUAs are modeled using the GNF2 (GEXL17) boiling correlation (Reference 9).

4.0 Discussion In this discussion, the TLO nomenclature is used for two recirculation loops in operation, and the SLO nomenclature is used for one recirculation loop in operation.

Table 2 provides the description of the current cycle and previous cycle for the reference loading pattern as defined by NEDE-24011-P-A (Reference 1).

4.1. Major Contributors to SLMCPR Change In general, for a given power-flow state point, the calculated safety limit is dominated by two key parameters: (1) flatness of the core bundle-by-bundle Minimum Critical Power Ratio (MCPR) distribution, and (2) flatness of the bundle pin-by-pin power/R-Factor distribution.

Greater flatness in either parameter yields more rods susceptible to boiling transition and thus a higher calculated SLMCPR. Therefore, the calculated SLMCPR may change whenever there are changes to the core configuration or to the fresh fuel designs. The plant-cycle specific SLMCPR methodology accounts for these factors.

The bundle designs and core loadings have been consistent since the GNF2 new fuel introduction in Cycle 15. The current SLMCPR TS values, which were established in Cycle 15, were based upon an older methodology. The newer reduced power distribution uncertainty methodology (References 2 and 3), which inherently results in a lower SLMCPR, was applied in Cycle 16 and Cycle 17. This plant has exhibited similar SLMCPR results over the past two cycles with this newer methodology (Table 1).

Discussion Page 6 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public) 4.2. Deviations from Standard Uncertainties Table 3 provides a list of deviations from NRC-approved uncertainties (References 2 and 3). A discussion of deviations from these NRC-approved values follows, all of which are conservative relative to NRC-approved values.

4.2.1. R-Factor GNF has generically increased the GEXL R-Factor uncertainty from (( )) to account for an increase in channel bow due to the phenomena called control blade shadow corrosion-induced channel bow, which is not accounted for in the channel bow uncertainty component of the approved R-Factor uncertainty. Reference 10 technically justifies that a GEXL R-Factor uncertainty of (( )) accounts for a channel bow uncertainty of up to

(( )). The LaSalle Unit 2 Cycle 17 analysis shows an expected channel bow uncertainty of (( )), which is bounded by a GEXL R-Factor uncertainty of (( )). Thus, the use of a GEXL R-Factor uncertainty of (( )) adequately accounts for the expected control blade shadow corrosion-induced channel bow. The effect of this change is considered not significant (i.e., < 0.005 increase on SLMCPR).

4.2.2. Core Flow Rate and Random Effective TIP Reading In Reference 11 GNF committed to the expansion of the state points used in the determination of the SLMCPR. Consistent with the Reference 11 commitments, GNF performs analyses at the rated core power and minimum licensed core flow point in addition to analyses at the rated core power and rated core flow point. The approved SLMCPR methodology is applied at each state point that is analyzed.

For the TLO calculations performed at 82.8% core flow, the approved uncertainty values for the core flow rate (2.5%) and the random effective Traversing In-Core Probe (TIP) reading (1.2%)

are conservatively adjusted by dividing them by 82.8/100.

The core flow and random TIP reading uncertainties used in the SLO minimum core flow SLMCPR analysis remain the same as in the rated core flow SLO SLMCPR analysis because these uncertainties (which are substantially larger than used in the TLO analysis) already account for the effects of operating at reduced core flow.

4.2.3. Flow Area Uncertainty GNF has calculated the flow area uncertainty for GNF2 using the process described in Section 2.7 of Reference 2. It was determined that the flow area uncertainty for GNF2 is conservatively bounded by a value of (( )). Because this is larger than the Reference 2 value of (( )) the bounding value was used in the SLMCPR calculations. The effect of this change is considered not significant (i.e., < 0.005 increase on SLMCPR).

Discussion Page 7 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public) 4.2.4. Fuel Axial Power Shape Penalty The GEXL correlation critical power uncertainty and bias are established for each fuel product line according to a process described in NEDE-24011-P-A (Reference 1).

GNF determined that higher uncertainties and non-conservative biases in the GEXL correlations for certain types of axial power shapes could exist relative to the NRC-approved methodology values (References 12, 13, and 14). GNF2 product lines are potentially affected in this manner only by Double-Hump (D-H) axial power shapes.

The D-H axial shape did not occur on any of the limiting bundles (i.e., those contributing to the 0.1% rods susceptible to transition boiling) in the current and/or prior cycle limiting cases.

Therefore, D-H power shape penalties were not applied to the GEXL critical power uncertainty or bias.

Discussion Page 8 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public) 5.0 References

1. Global Nuclear Fuel, General Electric Standard Application for Reactor Fuel, NEDE-24011-P-A, Revision 22, November 2015.

2. GE Nuclear Energy, Methodology and Uncertainties for Safety Limit MCPR Evaluations, NEDC-32601P-A, August 1999.

3. GE Nuclear Energy, Power Distribution Uncertainties for Safety Limit MCPR Evaluations, NEDC-32694P-A, August 1999.

4. GE Nuclear Energy, R-Factor Calculation Method for GE11, GE12 and GE13 Fuel, NEDC-32505P-A Revision 1, July 1999.

5. Letter, Frank Akstulewicz (NRC) to Glen A. Watford (GNF-A) Acceptance for Referencing of Licensing Topical Reports NEDC-32601P, Methodology and Uncertainties for Safety Limit MCPR Evaluations; NEDC-32694P, Power Distribution Uncertainties for Safety Limit MCPR Evaluation; and Amendment 25 to NEDE-24011-P-A on Cycle-Specific Safety Limit MCPR (TAC Nos. M97490, M99069 and M97491),

MFN-003-099, March 11, 1999.

6. Letter, Andrew A. Lingenfelter (GNF-A) to NRC Document Control Desk with cc to MC Honcharik (NRC), GNF2 Advantage Generic Compliance with NEDE-24011P-A (GESTAR II), NEDC-33270P, March 2007, and GEXL17 Correlation for GNF2 Fuel, NEDC-33292P, March 2007, FLN-2007-011, March 14, 2007.

7. Memorandum, Michelle C. Honcharik (NRC) to Stacy L. Rosenberg (NRC), Audit Report for Global Nuclear Fuels GNF2 Advantage Fuel Assembly Design GESTAR II Compliance Audit, September 25, 2008, (ADAMS Accession Number ML081630579).

8. Letter, Thomas H. Essig (NRC) to Glen A. Watford (GNF-A), Acceptance for Referencing of Licensing Topical Report NEDC-32505P, Revision 1, R-factor Calculation Method for GE11, GE12 and GE13 Fuel, (TAC Nos. M99070 and M95081), MFN-046-98, January 11, 1999.

9. Global Nuclear Fuel, GEXL17 Correlation for GNF2 Fuel, NEDC-33292P, Revision 3, April 2009.

10. Letter, John F. Schardt (GNF-A) to NRC Document Control Desk with attention to Mel B. Fields (NRC), Shadow Corrosion Effects on SLMCPR Channel Bow Uncertainty, FLN-2004-030, November 10, 2004.

11. Letter, Jason S. Post (GENE) to NRC Document Control Desk with attention to Chief, Information Management Branch, et al. (NRC), Part 21 Final Report: Non-Conservative SLMCPR, MFN 04-108, September 29, 2004.

References Page 9 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

12. Letter, Glen A. Watford (GNF-A) to NRC Document Control Desk with attention to Joseph E. Donoghue (NRC), Final Presentation Material for GEXL Presentation -

February 11, 2002, FLN-2002-004, February 12, 2002.

13. Letter, Glen A. Watford (GNF-A) to NRC Document Control Desk with attention to Alan Wang (NRC), NRC Technology Update - Proprietary Slides - July 31 - August 1, 2002, FLN-2002-015, October 31, 2002.

14. Letter, Jens G. Munthe Andersen (GNF-A) to NRC Document Control Desk with attention to Alan Wang (NRC), GEXL Correlation for 10X10 Fuel, FLN-2003-005, May 31, 2003.

References Page 10 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Table 1. Monte Carlo SLMCPR Previous Cycle Current Cycle Limiting Cases Limiting Cases Rated Power Rated Power Rated Power Rated Power Rated Description Minimum Core Flow Rated Core Flow Minimum Core Flow Core Flow Limiting Cycle Exposure Point Beginning of Cycle (BOC) /

EOC EOC EOC EOC Middle of Cycle (MOC) /

End of Cycle (EOC)

Cycle Exposure at Limiting Point 14660 14660 13100 13100 (MWd/STU)

((

))

Requested Change to the TS SLMCPR N/A1 1.12 (TLO) / 1.15 (SLO)

Note:

1. The TS SLMCPR for the previous cycle (Cycle 16) is based on the Cycle 15 TS SLMCPR (1.14 (TLO) / 1.17 (SLO)).

Table 1. Monte Carlo SLMCPR Page 11 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Table 2. Description of Core Description Previous Cycle Current Cycle Core Rated Power (MWt) 3546 3546 Minimum Flow at Rated Power 82.8% 82.8%

(% rated core flow)

Number of Bundles in the Core 764 764 Batch Sizes and Types:

(Number of Bundles in the Core)

Fresh Fresh: 264 GNF2, 4 GNF3 Fresh: 268 GNF2 Once-Burnt Once-Burnt: 304 GNF2 Once-Burnt: 264 GNF2, 4 GNF3 Twice-Burnt Twice-Burnt: 190 ATRIUM10 Twice-Burnt: 228 GNF2 Thrice-Burnt or more Thrice-Burnt: 2 ATRIUM10 Fresh Fuel Batch Average Enrichment 4.02 4.05 (Weight%)

Core Monitoring System 3DMonicore 3DMonicore Table 2. Description of Core Page 12 of 13

004N2839 R1-NP Non-Proprietary Information - Class I (Public)

Table 3. Deviations from Standard Uncertainties NRC Approved Value Description Previous Cycle Current Cycle

(%)

Power Distribution Uncertainties GEXL R-Factor (( )) (( )) (( ))

Random Effective TIP Reading All TLO Cases at Rated Power and 1.2 1.45 1.45 Minimum Flow Non-Power Distribution Uncertainties Channel Flow Area Variation (( )) (( )) (( ))

Total Core Flow Measurement All TLO Cases at Rated Power and 2.5 3.02 3.02 Minimum Flow Table 3. Deviations from Standard Uncertainties Page 13 of 13

Global Nuclear Fuel - Americas AFFIDAVIT I, Brian R. Moore, state as follows:

(1) I am the General Manager, Core & Fuel Engineering, Global Nuclear Fuel - Americas, LLC (GNF-A), and have been delegated the function of reviewing the information described in paragraph (2) which is sought to be withheld, and have been authorized to apply for its withholding.

(2) The information sought to be withheld is contained in GNF proprietary report 004N2839 R1-P, GNF Additional Information Regarding the Requested Changes to the Technical Specification SLMCPR LaSalle Unit 2 Cycle 17, dated May 2017. GNF proprietary information in 004N2839 R1-P is identified by a dotted underline placed within double square brackets. ((This sentence is an example.{3})) GNF proprietary information in some tables is identified with double square brackets before and after the object. In each case, the superscript notation {3} refers to Paragraph (3) of this affidavit, which provides the basis for the proprietary determination.