ML18347B493

Summary of Pre-Application Meeting with Exelon Generation Co., LLC (Exelon) Forthcoming License Amendment Requests to Revise Technical Specification Requirements for Main Steam Isolation Valve Leak Rate Tests

ML18347B493
Person / Time
Site:	Dresden, Nine Mile Point, Quad Cities, FitzPatrick
Issue date:	01/02/2019
From:	Haskell R Plant Licensing Branch III
To:	Bryan Hanson Exelon Generation Co, Exelon Nuclear
Haskell R, NRR/DORL/ LPL3, 415-1129
References
EPID L-2018-LRM-0088
Download: ML18347B493 (5)

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., ***ii"' January 2, 2019 LICENSEE: EXELON GENERATION COMPANY, LLC FACILITIES: QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2; DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3; NINE MILE POINT NUCLEAR STATION, UNIT 2; AND JAMES A. FITZPATRICK NUCLEAR POWER PLANT

SUMMARY

OF DECEMBER 6, 2018, PRE-APPLICATION MEETING WITH EXELON GENERATION COMPANY, LLC (EXELON) REGARDING FORTHCOMING LICENSE AMENDMENT REQUESTS TO REVISE TECHNICAL SPECIFICATION REQUIREMENTS FOR MAIN STEAM ISOLATION VALVE LEAK RATE TESTS (EPID L-2018-LRM-0088)

On December 6, 2018, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of Exelon Generation Company, LLC (Exelon). The meeting was held at the NRC Headquarters located in Rockville, Maryland. The purpose of the meeting was to discuss forthcoming license amendment requests (LARs) to in part, revise technical specification (TS) requirements for main steam isolation valve (MSIV) leak rate tests. Exelon's presentation entitled, "BWR [boiling water reactor] MSIV Leakage Optimization,"

available in the NRC Agencywide Documents Access and Management System (ADAMS)

(Accession No. ML18334A216) discussed potential changes due to TS Task Force Traveler TSTF-551, Revision 0, "Address Transient Secondary Containment Conditions," (ADAMS Accession No. ML14304A034), the elimination of delayed drywell bypass leakage, to no longer credit an MSIV leakage collection system, and the implementation of an alternate source term (AST). The nuclear power stations to be impacted by Exelon's proposed LARs are Quad Cities, Units 1 and 2; Dresden, Units 2 and 3; Nine Mile Point, Unit 2; and the James A. Fitzpatrick Power Plant (FitzPatrick). The meeting notice dated November 16, 2018, is available in ADAMS (Accession No. ML18338A303). A list of meeting attendees is enclosed.

This pre-application discussion was beneficial for both the NRC and Exelon staffs. The NRC staff gained a greater understanding of Exelon's approach to the BWR MSIV leakage optimization project. The Exelon staff took the opportunity to take note and to respond to NRC staff insights. Exelon's presentation included preliminary projections for the timelines of the LAR submittals. Exelon's proposed timelines are a function of each units scheduled outage weighted against typical NRC review periods for LARs (typically 12 months).

Several aspects of the discussion included generic information proposed for each of the LARs.

The NRG/Exelon staff discussed the re-evaluation and revision of TS MSIV leak rates. The NRG/Exelon staff discussed the re-evaluation of the design basis loss-of-coolant accident (LOCA) radiological analysis of record to be used to inform proposed MSIV leak rate limits. This includes ensuring Exelon addresses any other accident analyses of record (i.e., Updated Final Safety Analysis Report Chapter 15 events) or any unit safety limits potentially impacted by the proposed TS changes. The NRG/Exelon staff discussed the projected reductions of dose, maintenance/repair costs, and reportable events experienced during an outage. The NRG/Exelon staff discussed the potential usage of current NRC guidance as specified in

Regulatory Guide (RG) 1.183, Revision 0, "Alternative Radiological Source Terms for Evaluating Design-Basis Accidents at Nuclear Power Reactors," published July 2000 (ADAMS Accession No. ML003716792). The discussion included the Sandia National Laboratories Report, SAND2008-6601, "Analysis of Main Steam Isolation Valve Leakage in Design Basis Accidents Using MELCOR 1.8.6 and RADTRAD," dated October 2008 (Accession No. ML083180196).

The NRC staff stressed that further discussions with Exelon would be beneficial regarding these references. The NRG/Exelon staff discussed the need for each LAR to adequately provide justification for the proposed TS changes, to identify and justify any changes to the licensing basis accident analyses, and to provide ample details (e.g., assumptions and computer analyses input and output; relevant calculations, use of a data portal, etc.) to allow the NRC reviewers access to information needed to confirm the analysis. The NRC staff stressed this enhances the expediency to complete each review by mitigating the need for additional information in support of the review.

Several aspects of the discussion included site-specific information proposed to be in the LARs.

For instance, in the LARs for the Quad Cities and Dresden units, Exelon stated that they intend to propose new standby gas treatment system secondary containment drawdown calculations.

The calculations and associated analysis would support revised secondary containment TS surveillance requirements. The staff indicated that since Quad Cities and Dresden currently do not credit a secondary containment drawdown time, it would be of particular interest for Exelon to ensure the analysis is validated or for Exelon to demonstrate a sound bases to support the proposed TS changes. Exelon acknowledged the NRC staff's comments. In the LARs for Quad Cities, Dresden, and FitzPatrick, Exelon stated they intend to "decouple" the maximum allowable primary containment leakage rate from current TS requirements. For Nine Mile Point, Unit 2, Exelon intends to eliminate current TS requirements associated with delayed drywell leakage which is part of the unit's current licensing bases. Exelon indicated this should result in greater conservatisms factored into the MSIV bypass leakage for the unit. For the FitzPatrick unit, Exelon acknowledged a comment made by the NCR staff, that the LAR may require additional discussions due to the complexities associated with the proposed implementation of the unit's full-scope AST. The NRC staff stressed that previous LARs for AST implementations have benefited from pre-application meetings. This meeting would be a public meeting.

No regulatory decisions were made during this meeting. All feedback or comments expressed by the NRC staff during the meeting does not establish a regulatory position or constitute the acceptability of methodologies or changes discussed. One member of the public was in attendance. No public meeting feedback forms or comments have been received by the NRC staff.

Please direct any inquiries to me at 301-415-1129 or Russell.Haskell@nrc.gov.

Sincerely,;?;- ---~ ( *

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Russell Haskell II, Project Manager Plant Licensing Branch Ill Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-237, 50-249, 50-254, 50-265, 50-333, and 50-41 O

Enclosure:

List of Attendees cc: Listserv

LIST OF ATTENDEES DECEMBER 6 1 2018, MEETING WITH EXELON GENERATION COMPANY, LLC Name Affiliation Jennifer Whitman NRC Caroline Tilton NRC Matthew Hamm NRC Kristy Bucholtz NRC Fred Forsatv NRC Mark Blumberg NRC Booma Venkataraman NRC Kevin Hsueh NRC Muhammad Razzaque NRC Zeechung Wang NRC Russell Haskell NRC Christian Williams EXELON John Massari EXELON Shane Gardner EXELON Chong Zhou EXELON Daniel Lee EXELON Kathrine Leaveck EXELON Mitch Mathews EXELON Patrick Simpson EXELON Rachel Luebbe EXELON Rebecca Steinman EXELON Thomas Wojcik EXELON Tom McMahon EXELON Guy Foster EXELON Jeffrey Head ENERCON Joanne Morris ENERCON Marvin Morris ENERCON Sam LaFountain ENERCON Jana Bergman CURTISS-WRIGHT Enclosure

ML183478493 OFFICE NRR/D0RL/LPL3/PM NRR/D0RL/LPL3/LA NRR/D0RL/LPL3/BC NRR/D0RL/LPL3/PM NAME RHaskell $Rohrer DWrona RHaskell DATE 12/13/18 12/13/18 01/02/19 01/02/19