ML19283C553

Redacted - Brunswick Steam Electric Plant, Units 1 and 2 - Request for Additional Information

ML19283C553
Person / Time
Site:	Brunswick
Issue date:	10/18/2019
From:	Andrew Hon Plant Licensing Branch II
To:
Hon A, 415-8480
Shared Package
ML19283C829	List: ML19283C553
References
EPID L-2018-LLA-0273
Download: ML19283C553 (3)

Text

PROPRIETARY INFORMATION REQUEST FOR ADDITIONAL INFORMATION By letter dated October 11, 2018, Duke Energy submitted a license amendment request for Brunswick Steam Electric Plant, Units 1 and 2 (BSEP) to allow application of the Framatome analysis methodologies necessary to support a planned transition to ATRIUM 11 fuel under the currently licensed Maximum Extended Load Line Limit Analysis Plus (MELLLA+) operating domain [1]. Upon review of the submittal, the NRC staff has determined the following information is needed to complete its review.

The proprietary information in this document is marked with double brackets and bold font such as ((Example)).

Regulatory Bases The plant-specific Best Estimate Enhanced Option-III (BEO-III) Long Term Stability Solution (LTSS) and related licensing basis were developed to comply with the requirements of General Design Criteria (GDCs) 10 and 12 in Part 50 of Title 10 of the Code of Federal Regulations (10 CFR), Appendix A, General Design Criteria for Nuclear Power Plants.

Criterion 10, Reactor design, requires that: The reactor core and associated coolant, control, and protection systems shall be designed with appropriate margin to assure that specified acceptable fuel design limits [(SAFDLs)] are not exceeded during any condition of normal operation, including the effects of anticipated occurrences.

Criterion 12, Suppression of reactor power oscillations, requires that: The reactor core and associated coolant, control, and protection systems shall be designed to assure that power oscillations which can result in conditions exceeding specified acceptable fuel design limits are not possible or can be reliably and readily detected and suppressed.

Based upon its review to date, the NRC staff has made a preliminary determination that the plant-specific BEO-III calculation procedure in ANP-3703P (Attachment 15 to [1]) with the period based density algorithm (PBDA), combined with the calculation procedure in DPC-NE-1009-P (Attachment 16 to [1]) with the confirmation density algorithm (CDA), provides an acceptable means of determining licensing-basis safety limit minimum critical power ratio (SLMCPR) protection during anticipated stability events at BSEP. However, the NRC staffs preliminary determination relies upon the assumption that the following six conditions are met.

Information Request

1. ((

))

2. Cycle-specific statistical analyses shall address all parameters shown in Table 1 in accordance with the uncertainty distributions defined in ANP-3703P and the licensees response to RAI-26 [2].

PROPRIETARY INFORMATION

PROPRIETARY INFORMATION Table 1: Modeling Parameters Included in the BEO-III Statistical Analysis Category Parameter PIRT Importance

3. Cycle-specific analyses shall (( ))

4. ((

PROPRIETARY INFORMATION

PROPRIE:T/\RY INFORM/\TIO~~

)) is permissible, in terms of compliance with General Design Criteria 10 and 12, provided that the licensee ensures, with significant margin, that ((

))

5. In performing cycle-specific analyses with the CDA, a reduced analysis using the minimum population requirement described in DPC-NE-1009-P, "Brunswick Nuclear Plant Implementation of Best-Estimate Enhanced Option-Ill," that may permit the exclusion of some trials with a final over initial (F/1) MCPR less than 1.0 is appropriate only for specific events that have been demonstrated to be non-limiting with significant margin in the cycle-specific BE0-111 analysis using the PBDA. Otherwise, a more comprehensive analysis shall be performed using the CDA; for example, using the requirement to analyze all cases for the given event(s) with F/1 MCPR less than 1.0.

6. Selected settings and modeling options, including core and vessel nodalization, time step control parameters, and noise parameters, shall be defined consistently with the characteristics of the plant and the validation basis provided in ANP-3703P.

To assure the acceptability of the proposed plant-specific BE0-111 calculation procedure, please (1) propose a regulatorily binding means of ensuring that these conditions will be followed for all future calculations performed with the proposed plant-specific BE0-111 calculation procedure, (2) propose implementation of equivalent alternatives that would accomplish the underlying purpose of the conditions listed above, or (3) justify that the conditions listed above are not necessary to assure acceptability.

References

[1] Duke Energy, "Brunswick, Units 1 and 2, Request for License Amendment Regarding Application Of Advanced Framatome Methodologies", October 11, 2018, ADAMS Package Accession No. ML18284A394.

[2] Duke Energy, ANP-3782P, Revision 1, Brunswick, Units 1 and 2, Response to Request for Additional Information Regarding Advanced Framatome Methodologies License Amendment Request, May 29, 2019, ML19149A320.

PROPRIE:TARY l~~FORMATION