ML15008A273

NRR E-mail Capture - Draft RAI for Mur (Steam Generator Branch)

ML15008A273
Person / Time
Site:	Catawba
Issue date:	01/08/2015
From:	Geoffrey Miller Plant Licensing Branch II
To:	Rudy L Duke Energy Corp
References
TAC MF4526, TAC MF4527
Download: ML15008A273 (3)

Text

NRR-PMDAPEm Resource From: Miller, Ed Sent: Thursday, January 08, 2015 1:19 PM To: 'lawrence.rudy@duke-energy.com'

Subject:

Draft RAI for MUR (Steam Generator Branch)

Attachments: DRAFT Catawba MUR ESGB RAI_2.docx

Larry, The NRC staffs draft RAI for the subject relief request is attached to this e-mail. The draft RAI is not an official NRC staff request and is being provided to you to facilitate a subsequent conference call to determine: 1) If the questions clearly convey the NRC staff information needs; 2) Whether the regulatory basis for the questions is understood; 3) Whether the information is already available in existing, docketed, correspondence; and 4) To determine an appropriate response time-frame. After youve had a chance to review the draft information request, please contact me to schedule the conference call.

Ed Miller (301) 415-2481 1

Hearing Identifier: NRR_PMDA Email Number: 1805 Mail Envelope Properties (9C2386A0C0BC584684916F7A0482B6CA012F30B03F8A)

Subject:

Draft RAI for MUR (Steam Generator Branch)

Sent Date: 1/8/2015 1:18:40 PM Received Date: 1/8/2015 1:18:00 PM From: Miller, Ed Created By: Ed.Miller@nrc.gov Recipients:

"'lawrence.rudy@duke-energy.com'" <lawrence.rudy@duke-energy.com>

Tracking Status: None Post Office: HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 672 1/8/2015 1:18:00 PM DRAFT Catawba MUR ESGB RAI_2.docx 27466 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

REQUEST FOR ADDITIONAL INFORMATION CATAWBA NUCLEAR STATION UNITS 1 & 2 MEASUREMENT UNCERTAINTY RECAPTURE (MUR) POWER UPRATE DUKE ENERGY CAROLINAS COMPANY DOCKET NOS. 50-413 & 50-414 TAC NOS. MF4526 & MF4527 By letter dated June 23, 2014, Duke Energy Carolinas, LLC (Duke Energy), the licensee for Catawba Nuclear Station Units 1 and 2 (Catawba), requested a Measurement Uncertainty Recapture (MUR) Power Uprate. (Agencywide Document Access and Management System (ADAMS) Accession Numbers ML14176A109). The proposed revision would increase Catawba Unit 1s authorized core power level from 3411 megawatts thermal (MWt) to 3469 MWt, an increase of 1.7% Rated Thermal Power (RTP).

Based on the review of the amendment request, the NRC has determined that additional information is required regarding the MUR power uprate.

ESGB - RAI 3 Describe the evaluations performed to assess the potential impact of the power uprate on steam generator (SG) tube vibration response and consequential wear degradation (wear at tube support locations, tube-to-tube wear) and fatigue. This should include a description of the impact of the power uprate on average and peak thermal hydraulic parameters (e.g., gap velocities, dynamic pressures, void fractions, and steam quality) and how these were considered in assessing tube wear and fatigue performance. This should also include a discussion of whether these thermal hydraulic conditions are within the envelope of successful experience at other plants of similar design and size. Successful experience in this context refers to avoiding rapidly developing degradation mechanisms that cannot be successfully managed through the SG Program.