ML14295A454

RAI Information Regarding License Amendment Request Conditional Exemption of the End of Cycle Moderator Temperature Coefficient Measurement Methodology

ML14295A454
Person / Time
Site:	Catawba, McGuire, Mcguire
Issue date:	10/24/2014
From:	Geoffrey Miller Plant Licensing Branch II
To:	Capps S, Henderson K Duke Energy Carolinas
Miller G
References
TAC MF3119, TAC MF3120, TAC MF3121, TAC MF3122
Download: ML14295A454 (5)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 24, 2014

.Mr. Kelvin Henderson Site Vice President Catawba Nuclear Station Duke Energy Carolinas, LLC 4800 Concord Road York, SC 297 45 Mr. Steven D. Capps Vice President McGuire Nuclear Station Duke Energy Carolinas, LLC 12700 Hagers Ferry Road Huntersville, N.C 28078

SUBJECT:

CATAWBA NUCLEAR STATION, UNITS 1 AND 2 AND MCGUIRE NUCLEAR STATION, UNITS 1 AND 2- REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST RE: CONDITIONAL EXEMPTION OF THE END OF CYCLE MODERATOR TEMPERATURE COEFFICIENT MEASUREMENT METHODOLOGY (TAC NOS. MF3119, MF3120, MF3121, AND MF3122)

Dear Mr. Henderson and Mr. Capps:

By letter dated May 31, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12153A328), Duke Energy Carolinas, LLC (Duke), submitted a license amendment request for Catawba Nuclear Station, Units 1 and 2, and McGuire Nuclear Station, Units 1 and 2. The proposed amendment'requested review and approval of a conditional exemption to the performance of surveillance requirement 3.1.3.2 provided certain benchmark criteria are met. ByI letter dated March 13, 2013 (ADAMS Accession No. *.

ML13074A304), Duke provided a response to NRC staff requests for additional information (RAis) on the subject amendment request.

The U.S. Nuclear Regulatory Commission (NRC) staff is reviewing your submittal and response and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The RAI questions were provided in draft form to Duke on October 8, 2014. The draft questions were sent to facilitate a teleconference to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed.

On October 20, 2014, Duke staff indicated that they could respond within 30 days from the date of this letter.

K. Henderson and S. Capps If you have any questions regarding this matter, I may be reached at (301) 415-2481 or by e-mail at ed.miller@nrc.gov.

Sin;'( j L>DD'1/" "

G. Edward Miller, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-369, 50-370, 50-413, and 50-414

Enclosure:

As Stated cc w/encl: Distribution via Listserv

DRAFT REQUEST FOR ADDITIONAL INFORMATION MCGUIRE NUCLEAR STATION, UNITS 1 AND 2 CATAWBA_ NUCLEAR STATION, UNITS 1 AND2 RELATED TO TOPICAL REPORT DPC-NE-1007-P METHODOLOGY FOR CONDITIONAL EXEMPTION OF EOC MTC MEASUREMENT DOCKET NOS. 50-369, 50-370, 50-413, AND 50-414 By letter dated May 31, 2012, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12153A328), Duke Energy Carolinas (Duke) submitted a license amendment request (LAR) to amend the Technical Specifications (TS) 5.6.5, "Core Operating Limits Report (COLR)," for McGuire Nuclear Station, Units 1 and 2, and Catawba Nuclear Station, Units 1 and 2. In order for the NRC staff to complete its review of the LAR, the following additional information is requested.

By letter dated March 13, 2013 (ADAMS Accession No. ML13074A304), Duke provided a response to NRC staff requests for additional information (RAis) on the subject amendment request. Please note that the numbering of these RAis is continued from the previous set of RAis, issued January 22, 2013. The first RAI in this set is RAI 10.

RAI 10. As discussed in both the question of and response to RAI 4 from the previous set of NRC RAis, there is a bias between the measured and predicted values of the end of cycle (EOC) hot full power (HFP) moderator temperature coefficient (MTC).

(a) How is this bias included in the predicted MTC term of Equation 3 in Table 3-5?

A negative bias in the measured minus predicted values of MTC means that, on average, measured MTC is closer to the most negative MTC limit than predicted MTC. This bias is, therefo"re, nonconservative when using the predicted value of MTC as a substitute for the measurement.

(b) How vvill this bias be reevaluated when modifications are made to either core design codes or the core design itself (e.~., new fuel types, loading patterns, cycle lengths, burnable absorbers, etc.)? *

• RAI 11. As discussed in RAI 2 from the previous set of NRC RAis, there is a bias between the measured and predicted values of the beginning of cycle (BOC) hot zero power (HZP) isothermal temperature coefficient (lTC). In reviewing Figures 3-2 through 3-4, as well as the information about the BOC HZP lTC data presented in Section 3.5, it appears that this bias was not accounted for in the development of the BOC HZP lTC acceptance criterion, either as originally presented or in the revised criterion given in the response to RAI 2. Failure to account for this bias results in acceptance criteria 1 During the October 20, 2014, draft RAI teleconference, Duke staff identified that information responsive to this question was contained in their response to RAI 5 of the previous NRC staff information request. No further information is requested with respect to RAI 1O(b).

Enclosure

where values of measured minus predicted lTC may be found acceptable even if they are far (several standard deviations) from the operating experience base.

If the bias has been accounted for in the development of the BOC HZP lTC acceptance criterion, please discuss how this was accomplished. If it has not been accounted for, please either justify continued use of the proposed acceptance criterion

• or propose new limits that take the bias into account.

RAI 12. The proposed predicted-to-measured MTC uncertainty developed in Section 3.5, and particularly the value discussed on pages 3-8 and 3-9, requires additional quantitative justification. Specifically, an estimate of the measurement uncertainty for previous EOC HFP MTC measurements should be provided to enable the NRC staff to determine the acceptability of the measurement uncertainty used in the analysis. Any justification should also discuss the points in Figures 3-5 and 3-6 that are not bounded by the proposed uncertainty.

ML14295A454 *via e-mail OFFICE N RR/DORLILPL2-1 /PM NRR/DORLILPL2-1/LA . NRR/DSS/SNPB/BC NAME GEMiller SFigueroa (SRohrer for) JDean*

DATE 10/23/14 10/23/14 10/03/14 OFFICE NRR/DORLILPL2-1/BC NAME RPascarelli DATE 10/24/14