ML20086G480

NRR E-mail Capture - Request for Additional Information for WBN2 Request Measurement Uncertainty Recapture Power Uprate (L-2019-LLS-0000) - Part 2

ML20086G480
Person / Time
Site:	Watts Bar
Issue date:	03/26/2020
From:	Kimberly Green NRC/NRR/DORL/LPL2-2
To:	Wells R Tennessee Valley Authority
References
L-2019-LLS-0000
Download: ML20086G480 (3)

Text

From: Green, Kimberly Sent: Thursday, March 26, 2020 7:19 AM To: Wells, Russell Douglas Cc: Shoop, Undine

Subject:

Request for Additional Information for WBN2 Request Measurement Uncertainty Recapture Power Uprate (L-2019-LLS-0000) - Part 2 Attachments: WBN2 MUR RAI EMIB-2.docx

Dear Mr. Wells,

By letter dated October 10, 2019 (Agencywide Documents Access and Management System Accession No. ML19283G117), Tennessee Valley Authority (TVA) submitted a license amendment request (LAR) for the Watts Bar Nuclear Plant, Unit 2. The proposed amendment would increase the authorized core power level by approximately 1.4 percent rated thermal power from 3411 megawatts thermal (MWt) to 3459 MWt. Additionally, the proposed amendment would revise Technical Specification (TS) 1.1, Definitions, and TS 5.9.5b, Core Operating Limits Report (COLR), to reflect changes to the power level and use of the leading edge flowmeter (LEFM).

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.

A draft request for additional information (RAI) was previously transmitted to you by email dated March 12, 2020 (ADAMS Accession No. ML20083J395). At your request, a clarification call was held on March 19th to clarify the NRC staffs requests. Based on the discussion during that call, the NRC staff has reviewed information in TVAs LAR regarding flow-induced vibration and has revised RAI EMIB-2 to refer to the LAR rather than guidance in Regulatory Guide 1.20, Comprehensive Vibration Assessment Program for Reactor Internals During Preoperational and Initial Startup Testing, Revision 4, and in Nuclear Energy Institute (NEI) 08-10, Roadmap for Power Uprate Program Development and Implementation, Revision 0.

A response to the attached RAI is requested no later than April 30, 2020.

The NRC staff considers that timely responses to RAIs help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1627 or via email at Kimberly.Green@nrc.gov.

Sincerely, Kim Green (301) 415-1627 kimberly.green@nrc.gov

Hearing Identifier: NRR_DRMA Email Number: 495 Mail Envelope Properties (MN2PR09MB58200442EC13AE4250CCF54E8FCF0)

Subject:

Request for Additional Information for WBN2 Request Measurement Uncertainty Recapture Power Uprate (L-2019-LLS-0000) - Part 2 Sent Date: 3/26/2020 7:18:54 AM Received Date: 3/26/2020 7:18:00 AM From: Green, Kimberly Created By: Kimberly.Green@nrc.gov Recipients:

"Shoop, Undine" <Undine.Shoop@nrc.gov>

Tracking Status: None "Wells, Russell Douglas" <rdwells0@tva.gov>

Tracking Status: None Post Office: MN2PR09MB5820.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 2116 3/26/2020 7:18:00 AM WBN2 MUR RAI EMIB-2.docx 29894 Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

REQUEST FOR ADDITIONAL INFORMATION TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNIT 2 DOCKET NO. 50-391 MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE By letter dated October 10, 2019 (Agencywide Documents Access and Management System Accession No. ML19283G117) to the U.S. Nuclear Regulatory Commission, Tennessee Valley Authority submitted a license amendment request (LAR) for the Watts Bar Nuclear Plant, Unit 2 (WBN2). The proposed amendment would increase the authorized core power level by approximately 1.4 percent rated thermal power from 3411 megawatts thermal (MWt) to 3459 MWt. Additionally, the proposed amendment would revise Technical Specification (TS) 1.1, Definitions, and TS 5.9.5b, Core Operating Limits Report (COLR), to reflect changes to the power level and use of the leading edge flowmeter.

RAI EMIB-2 The WBN2 measurement uncertainty recapture (MUR) LAR, Table IV.1-1, shows that for analyzed MUR power uprate Cases 1 and 2 the total steam outlet flow is increased. The WBN2 MUR LAR, Sections, IV.1.B.iii, Flow Induced Vibration, and IV.1.F, related to Steam Generator Tubing, do not discuss any evaluation of safety-related components in the steam system due to increased steam flow. Please explain how the adverse effects from flow-induced vibration of safety-related components in the steam system were evaluated due to increased steam flow.