RA-21-0021, 30-Day Report Pursuant to 10 CFR 50.46, Changes to or Errors in an Acceptable Loss of Coolant Evaluation Model

30-Day Report Pursuant to 10 CFR 50.46, Changes to or Errors in an Acceptable Loss of Coolant Evaluation Model

ML21040A383
Person / Time
Site:	Brunswick
Issue date:	02/09/2021
From:	Snider S Duke Energy Progress
To:	Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML21040A381	List: RA-21-0021, 30-Day Report Pursuant to 10 CFR 50.46, Changes to or Errors in an Acceptable Loss of Coolant Evaluation Model
References
RA-21-0021
Download: ML21040A383 (12)

Text

Steve Snider Vice President Nuclear Engineering 526 South Church Street, EC-07H Charlotte, NC 28202 980-382-6195 Steve.Snider@duke-energy.com PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 UPON REMOVAL OF ENCLOSURE 2 THIS LETTER IS UNCONTROLLED Serial: RA-21-0021 10 CFR 50.46(a)(3)(ii)

February 9, 2021 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Brunswick Steam Electric Plant, Unit Nos. 1 and 2 Renewed Facility Operating License Nos. DPR-71 and DPR-62 Docket Nos. 50-325 and 50-324

SUBJECT:

30-Day Report Pursuant to 10 CFR 50.46, Changes to or Errors in an Acceptable Loss of Coolant Evaluation Model

REFERENCES:

1. Duke Energy Progress, LLC letter to NRC, Supplement to Request for License Amendment Regarding Application of Advanced Framatome Methodologies, dated July 2, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML19183A108)

2. NRC letter to Duke Energy Progress, LLC, Brunswick Steam Electric Plant, Units 1 and 2 - Issuance of Amendment Nos. 299 And 327 to Revise Technical Specification 5.6.5b to Allow Application of Advanced Framatome Atrium 11 Fuel Methodologies (EPID L-2018-LLA-0273), dated March 6, 2020 (ADAMS Accession No. ML20073F186)

Ladies and Gentlemen:

10 CFR 50.46(a)(3)(ii) requires the reporting of changes to or errors in Emergency Core Cooling System (ECCS) evaluation models (EMs), or in the application of such models that affect the temperature calculation. As such, Duke Energy Progress, LLC (Duke Energy) hereby submits information regarding the results of a reanalysis of the Brunswick Steam Electric Plant Unit Nos.

1 and 2 (BNP) Loss of Coolant Accident (LOCA) methodology for ATRIUM 11 fuel, considering discovery of a -75°F change.

This submittal satisfies the notification of a significant change, as required by 10 CFR 50.46(a)(3)(ii), due to a greater than 50°F change in the AURORA-B LOCA methodology calculated peak cladding temperature (PCT). The BNP licensing basis PCT was established as 1957°F in a letter to NRC dated July 2, 2019 (Reference 1), which supplemented the License Amendment Request to support loading Framatome ATRIUM 11 fuel, as approved by NRC in letter dated March 6, 2020 (Reference 2). Enclosure 1 contains a discussion of changes to the BNP ATRIUM 11 fuel LOCA analyses and establishes a new licensing basis PCT of 1882°F.

Enclosures 2 and 3 contain the proprietary and non-proprietary details, respectively, of the error.

PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 UPON REMOVAL OF ENCLOSURE 2 THIS LETTER IS UNCONTROLLED

PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 UPON REMOVAL OF ENCLOSURE 2 THIS LETTER IS UNCONTROLLED U.S. Nuclear Regulatory Commission RA-21-0021 Page 2 provides an affidavit from Framatome supporting the request for withholding information in Enclosure 2 from public disclosure.

Since the changes in PCT were significant, a schedule for providing a reanalysis or other actions to show compliance with 10 CFR 50.46 as discussed in 10 CFR 50.46(a)(3)(ii) is required. BNP will complete a full LOCA reanalysis, with the newly identified error included, prior to startup after the Unit 1 Cycle 24 outage, no later than June 1, 2022. The date of June 1, 2022 is chosen based on the planned action by Framatome to deliver an updated BNP LOCA report in November 2021, and additional time for Duke Energy to implement the reanalysis.

There are no new regulatory commitments contained in this submittal.

If you have additional questions, please contact Mr. Art Zaremba, Manager - Regulatory Affairs, at 980-373-2062.

Sincerely, Steve Snider Vice President - Nuclear Engineering

Enclosures:

1. Discussion of Changes to LOCA Analyses

2. Description of AURORA-B LOCA Methodology Error (Proprietary)

3. Description of AURORA-B LOCA Methodology Error (Non-Proprietary)

4. Framatome, Inc. Affidavit cc:

L. Dudes, Regional Administrator USNRC Region II A. Hon, NRR Project Manager - BNP G. Smith, USNRC Senior Resident Inspector for BNP General Counsel to Chair of NC Utilities Commission (swatson@ncuc.net)

W. L. Cox III (lee.cox@dhhs.nc.gov), NC DHHS P. D. Cox (patrick.cox@dhhs.nc.gov), NC DHHS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 UPON REMOVAL OF ENCLOSURE 2 THIS LETTER IS UNCONTROLLED RA-21-0021 Enclosure 1 Discussion of Changes to LOCA Analyses RA-21-0021 A new Licensing Basis Analysis of Record for ATRIUM 11 LOCA Analysis (Reference 1) was implemented to support operation of ATRIUM 11 fuel. Per Reference 1, the ATRIUM 11 Licensing Basis PCT was calculated to be 1957°F at 0 GWd/MTU exposure. One subsequent error notice on this ATRIUM 11 analysis was received, Reference 2.

The ATRIUM 11 error notice (Reference 2) documents 7 new evaluations with a cumulative impact of -75°F, bringing the ATRIUM 11 PCT to 1882°F. This notice includes the -5°F ATRIUM 11 impact previously reported to Duke Energy in Reference 3. Additionally, four of the evaluations resulted in a 0°F PCT impact (issue with AUTOSR5LOCA axial power shapes, coding issue in RODEX4 model for pellet gap condition, issue with AUTOBLT pressure location for SRV controller, and issue with AUTOSR5BDK-LOCA heat structure initialization) and one resulted in a +5°F PCT impact (error identified in MICROBURN-B2 loss coefficient for the upper tie plate (UTP)).

One error in S-RELAP5 resulted in a PCT impact of -75°F. S-RELAP5 is the computer code used within the AURORA-B LOCA methodology to perform the break spectrum analysis. The proprietary and non-proprietary description of the AURORA-B LOCA methodology error is contained in Enclosures 2 and 3, respectively, of this letter.

References:

1) Framatome Report ANP-3674P, Brunswick Units 1 and 2 LOCA Analysis for ATRIUM 11 Fuel, Revision 2, May 2019

2) FS1-0052486 Revision 2.0, 10 CFR 50.46 PCT Error Report for Brunswick Units 1 and 2 ATRIUM 11 Fuel, Framatome Inc., January 2021

3) FS1-0040060 Revision 2.0, 10 CFR 50.46 PCT Error Report for Brunswick Units 1 and 2 for MELLLA+ Operation, Framatome Inc., January 2020 RA-21-0021 ATRIUM11 Summary 10 CFR 50.46 Report for Brunswick Steam Electric Plant Unit 1 Plant: Brunswick Steam Electric Plant, Unit 1 Reporting Period: January 1, 2020 - December 31, 2020 LOCA Analysis Type (if applicable):

Evaluation Model: ANP-10332P-A, Revision 0 AURORA-B LOCA Evaluation Model, March 2019 Fuel: ATRIUM 11 (A11)

A. Analysis of Record PCT 1957 °F B. Net Cumulative 10 CFR 50.46 Net PCT Effect Absolute PCT Effect Changes and Error Corrections

- Previously Reported 0 °F 0 °F C. Baseline PCT for assessing new 1957 °F changes for significance (A + B)

D. Cumulative 10 CFR 50.46 Changes and Error Corrections

- This Reporting Period

1. RODEX4 Axial PCMI Onset -5 °F

2. AUTOSR5LOCA Axial Power +0 °F Shapes

3. RODEX4 Pellet Gap Condition +0 °F

4. AUTOBLT Pressure Location for +0 °F the SRV Controller

5. AUTOSR5BDK-LOCA Heat +0 °F Structure Initialization

6. S-RELAP5 CCFL Model -75 °F

7. MICROBURN-B2 UTP Loss +5 °F Coefficient E. Sum of 10 CFR 50.46 Changes and Net PCT Effect Absolute PCT Effect Error Corrections against Baseline

-75 °F 85 °F PCT F. Licensing Basis PCT (C + E) 1882 °F RA-21-0021 Enclosure 2 Description of AURORA-B LOCA Methodology Error (Proprietary)

Note: Text that is within bolded brackets is proprietary to Framatome.

RA-21-0021 Enclosure 3 Description of AURORA-B LOCA Methodology Error (Non-Proprietary)

Note: Text that is within bolded brackets is proprietary to Framatome and has been removed.

RA-21-0021 One error in S-RELAP5 resulted in a PCT impact of -75°F. S-RELAP5 is the computer code used within the AURORA-B LOCA methodology to perform the break spectrum analysis. An issue was identified during review of LOCA results that determined the [

] was not being applied appropriately in AURORA-B LOCA break spectrum analyses.

The [

]. Administration of the [

] as needed based on the applicable axial location for a modeled fuel bundle. Within S-RELAP5, the [

]. PCT estimates for the correct application [

] error resulted in a -75°F PCT change for the Brunswick ATRIUM 11 AURORA-B LOCA analysis.

RA-21-0021 Enclosure 4 Framatome Affidavit

A F FI D AVI T

1. My name is Alan 8. Meginnis. I am Manager, Product Licensing, for FramatomeInc. and as suchI am authorized to execute this Affidavit.

2. I am familiar with the criteria applied by Framatome to determine whether certain Framatome information is proprietary. I am familiar with the policies establishEd by Framatome to ensure the proper application of these criteria.

3. I am familiar with the Framatome information contained in the Enclosure 2 to Letter RA-21-0021 "30-Day Report Pursuant to 10 CFR 50.46, Changes to or Errors in an Acceptable Loss of Coolant Evaluation Model," dated February 2021 and referred to herein as "Document." Information contained in this Document has been classified by Framatorne as proprietary in accordance with the policies established by Framatome for the control and protection of proprietary and confidential information.

4. This Document contains information of a proprietary and confidential nature and is of the type customarily held in confidence by Framatome and not made available to the public. Based on my experience, I am aware that other companies regard information of the kind contained in this Document as proprietary and confidential.

5. This Document has been made available to the U.S. Nuclear Regulatory Commission in confidence with the request that the information contained in this Document be withheld from public disclosure. The request for withholding of proprietary information is made in accordance with 10 CFR 2.390. The information for which withholding from disclosure is requested qualifies under 10 CFR 2.390(a)(4) "Trade secrets and commercial or financial information."

6. The following criteria are customarily applied by Framatome to dete,rmine whether in rmation should be classified as proprietary:

a) The information reveals details of Framatome's research and deveh:>pment plans and programs or their results.

b) Use of the information by a competitor would permit the competitor to significantly reduce its expenditures, in time or resources, to design, produce, or market a similar product or service.

c) The information includes test data or analytical techniques concerning a process, methodology, or component, the application of which results in a competitive advantage for Framatome.

d) The information reveals certain distinguishing aspects of a process, methodology, or component, the exclusive use of which provides a competitive advantage for Framatome in product optimization or marketability.

e) The information is vital to a competitive advantage held by Framatome, would be helpful to competitors to Framatome, and would likely cause sub:stantial harm to the competitive position of Framatome.

The inform tion in the Document is considered proprietary for the reasons set forth in paragraphs 6(b), 6(d) and 6(e) above.

1. In accordance with Framatome's policies governing the protection and control of informatin, proprietary information contained in this Document have been made available, on a limited basis, to others outside Framatome only as required and under suitable a!reement providing for nondisclosure and limited use of the information.

Framatome policy requires that proprietary information be kept in a secured file or area and distributed on a need-to-know basis.

9. The foregoing statements are true and correct to the best of my knowledge, information, and belief.

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

Executed on: February 2, 2021

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