ML17079A101

NRC Pre-Submittal Meeting: Vogtle Electric Generating Plant - Units 1 and 2 License Amendment Request to Revise Technical Specification Surveillance Requirement 3.3.1.3 - March 23, 2017

ML17079A101
Person / Time
Site:	Vogtle
Issue date:	03/23/2017
From:	Florian R Southern Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation
Orenak M
Shared Package
ML17076A433	List: ML17076A432 ML17076A434 ML17079A101
References
Download: ML17079A101 (13)

Text

NRC PRE-SUBMITTAL MEETING Vogtle Electric Generating Plant - Units 1 and 2 License Amendment Request to Revise Technical Specification Surveillance Requirement 3.3.1.3 March 23, 2017 Prepared by Robert J. Florian

LICENSE AMENDMENT REQUEST CONTENT

• Cover letter

• Enclosure 1 - VEGP Basis for Proposed Change

• Enclosure 2 - VEGP Technical Specifications Marked-Up Pages

• Enclosure 3 - VEGP Technical Specifications Clean-Typed Pages

• Enclosure 4 - VEGP Technical Specifications Bases Marked-Up Page (Information Only) 3

SUMMARY

OF CONTENT OF ENCLOSURE 1 Table of Contents 1.0 Summary Description 2.0 Detailed Description 3.0 Technical Evaluation 4.0 Regulatory Evaluation 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 Significant Hazards Consideration Determination 4.4 Conclusions 5.0 Environmental Consideration 4

SUMMARY

OF CONTENT OF ENCLOSURE 1 1.0 Summary Description

• Proposes to revise VEGP TS 3.3.1.3.

• SR verifies the accuracy of the Axial Flux Difference (AFD) input to the reactor trip system as well as the indication of AFD for satisfying VEGP TS 3.2.3.

• NOTE in SR 3.3.1.3 states: Not required to be performed until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER is > 15% RTP.

• During power ascension following a refueling, SR is typically performed at about 30% RATED THERMAL POWER (RTP) where plant conditions allow for meaningful measurements.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 1.0 Summary Description (Continued)

• Once 15% RTP is reached, remainder of allowed time for performing the SR becomes challenging.

• Proposed to change power level in the NOTE from 15%

RTP to 50% RTP.

• This will provide sufficient time during power ascension after refueling to perform SR 3.3.1.3.

• Power level of 50% RTP is consistent with the power level at which AFD control is required by the safety analyses and TS 3.2.3.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 2.0 Detailed Description

• NOTE in SR 3.3.1.3 proposed to be revised to:

Not required to be performed until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER is > 50% RTP.

• SR performed to ensure that AFD input to OTT reactor trip function accurately reflects power distribution in core.

• SR also ensures accuracy of AFD indication to satisfy TS 3.2.3.

• Following a refueling outage, first performance of this SR not required until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER is >

15% RTP.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 2.0 Detailed Description (Continued)

• SR typically performed at about 30% RTP where plant conditions allow for meaningful measurements.

• If adjustment of instrument channels required, remainder of 24-hour time limit is restrictive and poses challenges to completing the SR.

• Threshold of 15% RTP is a historical value based on original (pre-ITS) VEGP Technical Specifications when AFD specification applicability began at 15% RTP.

• Power level of 50% RTP is consistent with power level at which AFD control is required by the safety analyses and TS 3.2.3.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 3.0 Technical Evaluation

• To obtain meaningful incore measurements, flux map needs to be taken at sufficiently high power level.

• Typically, this is at about 30% RTP following a refueling outage.

• Requirement in NOTE in SR 3.3.1.3 is challenging during power ascension following a refueling outage due to time required to raise power to about 30% RTP, place generator on line, stabilize reactor power, perform flux map, perform SR 3.3.1.3 to determine if the AFD channels meet acceptance criterion, and prepare information to perform adjustments, all within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after reaching 15% RTP.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 3.0 Technical Evaluation (Continued)

• In 1991, TS for AFD limits amended and applicability changed to 50% RTP.

• Threshold of 15% RTP for SR was not revised accordingly.

• During VEGP ITS conversion, 15% RTP threshold in SR was retained and 24-hour limit was added per STS.

• Power level of 50% RTP is consistent with power level at which AFD control is required by the safety analyses and TS 3.2.3.

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SUMMARY

OF CONTENT OF ENCLOSURE 1 4.0 Regulatory Evaluation

• Requirements of 10 CFR 50.36(c) continue to be met.

• General Design Criterion (GDC) 10, Reactor Design continues to be met.

• General Design Criterion (GDC) 20, Protection System Functions continues to be met.

• Review of precedent shows little consistency within Westinghouse fleet with power thresholds varying from 15%

RTP to 90% RTP and time limits varying from no limit up to 7 days.

• As required by 10 CFR 50.91(a)(1), SNC has determined that proposed amendment does not involve a significant hazards consideration using the standards of 10 CFR 50.92(c).

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SUMMARY

OF CONTENT OF ENCLOSURE 1 5.0 Environmental Consideration

• SNC has determined that proposed amendment meets eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9).

• Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with proposed amendment.

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OPEN DISCUSSION AND QUESTIONS 13