ML19098B091

Non Prop: Attachment 1 - Resolution of Comments Final Safety Evaluation for Westinghouse Electric Company Topic Report WCAP-18032-P, Revision 0, and WCAP-18032-NP, Revision 0, Calculation of Mixed Core Safety Limit Minimum Critical Power Ra

ML19098B091
Person / Time
Site:	Westinghouse
Issue date:	05/06/2019
From:	Ekaterina Lenning NRC/NRR/DLP/PLPB
To:
Lenning E, NRR/DLP, 415-3151
Shared Package
ML19094A033	List: ML19098B091
References
EPID L-2016-TOP-0015
Download: ML19098B091 (5)

Text

RESOLUTION OF COMMENTS ON DRAFT SAFETY EVALUATION FOR TOPICAL REPORT WCAP-18032-P, REVISION 0, AND WCAP-18032-NP, REVISION 0, CALCULATION OF MIXED CORE SAFETY LIMIT MINIMUM CRITICAL POWER RATIO WESTINGHOUSE ELECTRIC COMPANY By letter dated March 20, 2019 (Agencywide Documents Access and Management System Accession No. ML19084A084), Westinghouse Electric Company (Westinghouse) provided comments on the draft safety evaluation (SE) for Topical Report (TR) WCAP-18032-P, and Revision 0, WCAP-18032-NP, Revision 0, Calculation of Mixed Core Safety Limit Minimum Critical Power Ratio. Westinghouse stated that there is proprietary information in the draft SE.

The following is the U.S. Nuclear Regulatory Commission (NRC) staffs resolution of these comments:

Draft SE comments for TR WCAP-18032-P, and Revision 0, WCAP-18032-NP, Revision 0:

1. Westinghouse proposed to add the following sentence to the fifth paragraph of Section 3.1.2, Model Generation,:

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NRC Resolution for Comment 1 on Draft SE The NRC staff has reviewed the Westinghouse comment and agrees that proposed wording provides additional clarification. The NRC staff has updated the second sentence of the first paragraph of Section 1.0, Introduction.

The fifth paragraph of Section 3.1.2, Model Generation, reads now:

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Attachment 1

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2. First sentence of the twelfth paragraph of Section 3.1.2, Model Generation, reads:

Starting with an NRC-approved Westinghouse CPR model, X, Westinghouse will generate one or more of the following models depending one or more the legacy fuel CPR data available:

Westinghouse suggested that the first sentence of the twelfth paragraph of Section 3.1.2, Model Generation, should be re-worded to read:

Starting with an NRC-approved Westinghouse CPR model, X, Westinghouse will generate one or more of the following models depending on the legacy fuel CPR data availability:

NRC Resolution for Comment 2 on Draft SE The NRC staff has reviewed the Westinghouse comment and agrees that proposed wording provides additional clarification. The NRC staff has updated the first sentence of the twelfth paragraph of Section 3.1.2, Model Generation.

First sentence of the twelfth paragraph of Section 3.1.2, Model Generation, reads now:

Starting with an NRC-approved Westinghouse CPR model, X, Westinghouse will generate one or more of the following models depending on the legacy fuel CPR data availability:

3. Last paragraph of Section 3.1.2, Model Generation, reads:

Because Westinghouse will be starting with a previously approved CPR models mathematical form, applying a method to correlate R-factor parameters which is consistent with their currently approved approach, and potentially applying a method to optimizing model coefficients which are consistent with their currently approved approach (Case 2 and 3), the NRC staff has determined that the model has been generated in a logical fashion and goal G2 has been met.

Westinghouse suggested that the last paragraph of Section 3.1.2, Model Generation, should be re-worded to read:

Because Westinghouse will be starting with a previously approved CPR models mathematical form, applying a method to correlate R-factors and other model coefficients which is consistent with their currently approved approach, and potentially applying a method to optimizing model coefficients based on legacy data which is also consistent with their currently approved approach, the NRC staff has determined that the model has been generated in a logical fashion and goal G2 has been met.

NRC Resolution for Comment 3 on Draft SE The NRC staff has reviewed the Westinghouse comment and agrees that proposed wording provides additional clarification and consistency with the updates from Comment 1. The NRC staff has updated the last paragraph of Section 3.1.2, Model Generation.

Last paragraph of Section 3.1.2, Model Generation, reads now:

Because Westinghouse will be starting with a previously approved CPR models mathematical form, applying a method to correlate R-factors and other model coefficients which is consistent with their currently approved approach, and potentially applying a method to optimizing model coefficients based on legacy data which is also consistent with their currently approved approach, the NRC staff has determined that the model has been generated in a logical fashion and goal G2 has been met.

4. First sentence of the last paragraph of Section 3.1.3.1, Validation Error, reads:

Westinghouse identified the data used generate the validation error will be from either the legacy fuel vendor.

Westinghouse suggested that the first sentence of the last paragraph of Section 3.1.3.1, Validation Error, should be re-worded to read: Westinghouse has identified that the data used to generate the validation error will be from the legacy fuel vendor.

NRC Resolution for Comment 4 on Draft SE The NRC staff has reviewed the Westinghouse comment and agrees that proposed wording provides additional clarification. The NRC staff has updated first sentence of the last paragraph of Section 3.1.3.1, Validation Error, so it reads now: Westinghouse has identified that the data used to generate the validation error will be from the legacy fuel vendor.

5. Westinghouse proposed to insert the following proprietary sentences between the second sentence and third sentence of the second paragraph of Section 3.1.3.5.3, Transient Prediction:

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NRC Resolution for Comment 5 on Draft SE The NRC staff has reviewed the Westinghouse comment and agrees that proposed wording provides additional clarification. The NRC staff has updated the second paragraph of Section 3.1.3.5.3, Transient Prediction, which reads now:

For those instances when sufficient legacy fuel data is not available to ensure the error is adequately quantified in the transient domain, [

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6. Westinghouse provided proprietary markings on the draft SE.

NRC Resolution for Comment 6 on Draft SE:

The NRC staff reviewed the Westinghouse markings and incorporated them into the final SE.

7. Westinghouse provided editorial comments.

NRC Resolution for Comment 7 on Draft SE:

The NRC staff reviewed the Westinghouse comments and finds them acceptable because the changes are editorial in nature.