ML14133A684

NRR E-mail Capture - Request for Additional Information - Palisades Nuclear Plant 10 CFR 50 Appendix G Equivalent Margin Analysis - Mf 2962

ML14133A684
Person / Time
Site:	Palisades
Issue date:	05/13/2014
From:	Mahesh Chawla Division of Operating Reactor Licensing
To:	Erickson J Entergy Nuclear Operations
References
MF2962
Download: ML14133A684 (3)

Text

NRR-PMDAPEm Resource From: Chawla, Mahesh Sent: Tuesday, May 13, 2014 10:37 AM To: ERICKSON, JEFFREY S (JERICKS@entergy.com); DOTSON, BARBARA E (bdotson@entergy.com)

Cc: Carlson, Robert; Rosenberg, Stacey; Jenkins, Joel; Duncan, Eric; Scarbeary, April; Garmoe, Alex; Lennartz, Jay

Subject:

Request for Additional Information - Palisades Nuclear Plant 10 CFR 50 Appendix G Equivalent Margin Analysis - MF 2962 In the Palisades Nuclear Plant (Palisades) license renewal application, Agencywide Documents Access Management System (ADAMS) Accession No. ML050940446, Nuclear Management Company, the former license holder for Palisades, committed to submit an equivalent margins analysis (EMA) for approval at least three years before any reactor vessel beltline material Charpy upper-shelf energy (USE) decreases to less than 50 ft-lbs, in accordance with Title 10 of the Code of Federal Regulations, Part 50 Appendix G. By letter dated October 21, 2013, ADAMS Accession No. ML13295A448, Entergy Nuclear Operations, Inc. (Entergy, the licensee) submitted an EMA for Palisades, Westinghouse WCAP-17651-NP, Revision 0, Palisades Nuclear Power Plant Reactor Vessel Equivalent Margins Analysis, ADAMS Accession No. ML13295A451. In order to complete its review, the staff requires additional information.

Request of Additional Information (RAI-1):

The EMA is based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code)Section XI, Appendix K as supplemented by Regulatory Guide (RG) 1.161 Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less Than 50 Ft-Lb. ASME Code Section XI, Appendix K, Article K-4210 and RG 1.161 both include equations for calculating the stress intensity factor due to radial thermal gradients. In Section 5.1 of the EMA submittal, the licensee discusses through-wall thermal stress and states that typical through-wall stress and stress distribution during a heatup transient are shown in Figures 5-1 and 5-2. But Figures 5-1 and 5-2 of the EMA submittal do not show these stresses as discussed. Provide figures showing typical through-wall stress and stress distributions during a heatup transient to support the discussion in paragraph 5.1 of the EMA submittal.

RAI-2

Section 5.1 states, Only circumferential base metal flaws are considered in this analysis, because only the weak orientation USE is projected to drop below 50 ft-lbs as described below. Please demonstrate that assuming a circumferential flaw in the base metal with the weak Charpy V-Notch (CVN) value in the EMA is more limiting than assuming an axial flaw in the base metal with the strong CVN value. Please note that the significantly greater applied J-integral associated with the axial flaw may challenge the fundamental assumption in the EMA submittal.

RAI-3

The applied J-integral values for the circumferential flaws for all Level A and B service level conditions are shown in Figure 5-1, and the applied J-integral values for the circumferential flaws for Level C and D service level conditions are shown in Figure 5-2. Since Section 5.1 provides very limited information regarding the applied J-integral calculations, please 1

confirm that the calculations underlying Figures 5-1 and 5-2 are based on the formulas in RG 1.161, Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less Than 50 FT-LB. If not, please describe, in addition to your response to RAI-1, your plant-specific calculations to support their acceptance in this application.

RAI-4

Table 4-4 was presented but without being mentioned in Section 4 regarding how it was used in the EMA analysis. Therefore, please confirm that the calculated available margins presented in Table 5-3 for various time during cooldown are results, using the relevant J-R curves adjusted by the material margin factors of Table 4-4.

RAI-5

Section 5.2 provides justification for using the high-toughness/low-sulfur model from RG 1.161 in the proposed EMA for the high-sulfur plates, and Section 5.3 provides the corresponding EMA results. When the high-sulfur model (e.g., for the 6T specimen) of NUREG/CR-5265, Size Effects on J-R Curves for A 302-B Plate, is used, please demonstrate that

• The updated safety factors (see Table 5-3), after adjusting for temperature, will still be greater than 1.15.

• The updated applied J/J-R curves (see figures 5-8, 5-9, and 5-12), after adjusting for temperature, will still show that dJapplied/da < dJmaterial/da at Japplied = Jmaterial.

If the above cannot be demonstrated, perform a sensitivity study, showing at what percentage of the proposed J-R curve (e.g., 90%), your EMA calculation results will meet the criteria on both crack extension and stability.

RAI-6

Section 6 presents conclusions of this submittal. For Service Level C condition with 400°F/hr cooldown, it is concluded that, The equivalent margins analyses for the plate materials are acceptable and bounded by the conservative test data reported in NUREG/CR-5265 in all cases for the Level C transient. This conclusion was repeated later for Service Level D condition with 600°F/hr cooldown, with C in the quote replaced by D.

Plot the relevant NUREG/CR-5265 6T data in Figure 5-12 and provide sufficient justification to support your conclusions.

Please provide your response on docket within 30 days of the receipt of this request. In case you would like to discuss the above information, please arrange a teleconference with the NRC staff.

Thanks Mahesh Chawla Project Manager Phone: 301-415-8371 Fax: 301-415-1222 mahesh.chawla@nrc.gov 2

Hearing Identifier: NRR_PMDA Email Number: 1280 Mail Envelope Properties (Mahesh.Chawla@nrc.gov20140513103700)

Subject:

Request for Additional Information - Palisades Nuclear Plant 10 CFR 50 Appendix G Equivalent Margin Analysis - MF 2962 Sent Date: 5/13/2014 10:37:23 AM Received Date: 5/13/2014 10:37:00 AM From: Chawla, Mahesh Created By: Mahesh.Chawla@nrc.gov Recipients:

"Carlson, Robert" <Robert.Carlson@nrc.gov>

Tracking Status: None "Rosenberg, Stacey" <Stacey.Rosenberg@nrc.gov>

Tracking Status: None "Jenkins, Joel" <Joel.Jenkins@nrc.gov>

Tracking Status: None "Duncan, Eric" <Eric.Duncan@nrc.gov>

Tracking Status: None "Scarbeary, April" <April.Scarbeary@nrc.gov>

Tracking Status: None "Garmoe, Alex" <Alex.Garmoe@nrc.gov>

Tracking Status: None "Lennartz, Jay" <Jay.Lennartz@nrc.gov>

Tracking Status: None "ERICKSON, JEFFREY S (JERICKS@entergy.com)" <JERICKS@entergy.com>

Tracking Status: None "DOTSON, BARBARA E (bdotson@entergy.com)" <bdotson@entergy.com>

Tracking Status: None Post Office:

Files Size Date & Time MESSAGE 5370 5/13/2014 10:37:00 AM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

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