ML20094H029

Final: Dresden, Units 2 & 3 LAR Request for Additional Information to Modify Technical Specifications to Main Steam Isolation Valve Leakage Requirements

ML20094H029
Person / Time
Site:	Dresden
Issue date:	03/27/2020
From:	Haskell R Plant Licensing Branch III
To:	Steinman R Exelon Generation Co, Exelon Nuclear
Haskell R
References
EPID L-2019-LLA-0232
Download: ML20094H029 (2)

Text

From: Haskell, Russell To: Steinman, Rebecca L:(Exelon Nuclear)

Cc: "Mitchel.Mathews@exeloncorp.com"

Subject:

FINAL: Dresden, Units 2 & 3 Re: LAR Request for Additional Information to Modify Technical Specifications to Main Steam Isolation Valve Leakage Requirements (EPID L-2019-LLA-0232)

Date: Friday, March 27, 2020 9:01:00 AM Attachments: FINAL RAIs re Dresden MSIV Leakage LAR.docx

Dear Ms. Steinman,

By application dated October 21, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML19294A304), Exelon Generation Company, LLC (Exelon) requested changes to the technical specifications (TSs) for Dresden Nuclear Power Station, Units 2 and 3, to: (1) increase the individual main steam isolation valve (MSIV) leakage rate TS limit of < 34 standard cubic feet per hour (scfh) to < 62.4 scfh for Unit 2 and limit of < 34 scfh to 78 scfh for Unit 3; (2) revise the combined MSIV TS leakage rate of the four main steam lines from the TS limit of < 86 scfh to < 156 scfh for Unit 2 and from < 86 scfh to 218 scfh for Unit 3; (3) eliminate MSIV leakage to no longer be counted in the maximum allowable leakage rate for containment, requiring an exemption from the requirements of 10 CFR 50, Appendix J, Option B; (4) add a new TS 3.6.2.6, Drywall Spray requirement and credit the residual heat removal drywell spray system for fission product removal, and; (5) revise TS 3.6.4.1, Secondary Containment, to address secondary containment short-duration pressure conditions which is consistent with Technical Specification Task Force Traveler (TSTF) 551, Revision 3, Revise Secondary Containment Surveillance Requirements.

The U.S. Nuclear Regulatory Commission (NRC) staff is reviewing your submittal and has identified areas where additional information is needed to complete its review. Attached, please find requests for additional information (RAIs). On March 18, 2020, the NRC staff held a teleconference with you/your staff (incl. contractors) to discuss and resolve any associated clarifications of which a few discussions points were exchanged. At the conclusion of the call your staff agreed these RAIs were well understood and that no additional clarification(s) or text edits were necessary. Following the teleconference, the NRC added another RAI (i.e., ARCB-RAI-5) to address a calculation error identified in the application. You and I agreed this added RAI did not require any additional technical exchanges and was administratively included to correct docketed information. As such, the NRC staff will proceed by considering these RAIs to be final.

Therefore, the NRC staff is requesting for Exelon to provide docketed responses to these RAIs no later than the close of business on May 13, 2020, this represents at least a 45-day response period requested by Exelon. This should account for potential scheduling, coordination, or staffing related challenges due to the ongoing COVID-19 virus. Furthermore, this response time continues to support the NRC staffs evaluation to meet the projected fall 2020 outage schedule.

If you have any questions/comments, please contact me.

Thank you.

Russell S. Haskell II United States Nuclear Regulatory Commission (NRC)

Licensing Project Manager - NRR/DORL/LPL 3 Dresden Nuclear Power Station, Units 2 and 3

+ Russell.Haskell@NRC.Gov; ( (301) 415-1129; Office: O-8C01; Mail-Stop O-8B1A