ML17317A450

TSTF-568 Rev 0 Draft for 11/09/2017 Quarterly Meeting

ML17317A450
Person / Time
Site:	Technical Specifications Task Force
Issue date:	11/09/2017
From:	Technical Specifications Task Force
To:	Office of Nuclear Reactor Regulation
Honcharik M C
Shared Package
ML17317A453	List: ML17317A421 ML17317A424 ML17317A426 ML17317A447 ML17317A448 ML17317A449 ML17317A450
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Download: ML17317A450 (28)

Text

31-Oct-17 31-Oct-17

THERMAL POWER is > [15]% RTPTHERMAL POWER to < [15]% RTP italics with THERMAL POWER > [15]% RTP1. Not required to be met until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER > [15]% RTP.

2. Not required to be met 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to THERMAL POWER being reduced [15]% RTP.

with THERMAL POWER > [15]% RTP except within following sexceeds; andbelow planned

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NOTES ----------------------1. Not required to be met until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER > [15]% RTP.

2. Not required to be met 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to THERMAL POWER being reduced to [15]% RTP.---------------------------------------------------------

with THERMAL POWER > [15]% RTP except within following time periods:

exceeds; and belowduring planned

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NOTES ----------------------

1. Not required to be met until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after THERMAL POWER > [15]% RTP.

2. Not required to be met 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to THERMAL POWER being reduced to [15]% RTP. ---------------------------------------------------------------------

with THERMAL POWER > [15]% RTPthe potential for an event that generates significant hydrogen is low and the primary containment need not be inert. Furthermore, For the purposes of this Specification, a transition from MODE 2 to MODE 1 followed by a power ascension to above [15]% RTP is considered a startup. A reactor shutdown that results from a planned activity at least [24] hours prior to a power reduction to below [15]% RTP is considered a planned reactor shutdown for the purposes of this Specification.

This Surveillance is modified by two Notes. The first Note allows 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to inert the primary containment after increasing THERMAL POWER above [15]% RTP. The second Note allows 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to de-inert the primary containment prior to decreasing THERMAL POWER to less than or equal to [15]% RTP. The Notes take exception to the requirements of the Surveillance being met (i.e., establishing the drywell-to-suppression chamber differential pressure limits for this 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period). Inerting primary containment is an operational problem because it prevents primary containment access without an appropriate breathing apparatus. Therefore, the primary containment is inerted as late as possible in a unit startup and is de-inerted as soon as possible in a unit shutdown. As long as reactor power is [15]% RTP, the potential for an event that generates significant hydrogen is low and the primary containment need not be inert. Furthermore, the probability of an event that generates hydrogen or excessive loads on primary containment occurring within the [24] hours following exceeding [15] RTP, or within [24] hours prior to reducing THERMAL POWER to less than or equal to [15]% RTP, is low enough that these "windows," with the primary containment not inerted, are also justified. The [24] hour time period is a reasonable amount time to allow plant personnel to perform inerting or de-inerting.

with THERMAL POWER

> [15]% RTP

[]reactor

For the purposes of this Specification, a transition from MODE 2 to MODE 1 followed by a power ascension to above [15]% RTP is considered a startup. A reactor shutdown that results from a planned activity at least [24] hours prior to a power reduction to below [15]% RTP is considered a planned reactor shutdown for the purposes of this Specification.

above [15]% RTP

This Surveillance is modified by two Notes. The first Note allows 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to inert the primary containment after increasing THERMAL POWER above [15]% RTP. The second Note allows 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to de-inert the primary containment prior to decreasing THERMAL POWER to less than or equal to [15]% RTP. The Notes take exception to the requirements of

the Surveillance being met (i.e., establishing the primary containment oxygen concentration limits for this 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period). Inerting the primary containment is an operational problem because it prevents containment access without an appropriate breathing apparatus. Therefore, the primary containment is inerted as late as possible in a plant startup and de-inerted as soon as possible in a plant shutdown. As long as reactor power is [15]% RTP, the potential for an event that generates significant hydrogen is low and the primary containment need not be inert. Furthermore, the probability of an event that generates hydrogen occurring within [24] hours following exceeding [15]% RTP, or within [24] hours prior to reducing THERMAL POWER to less than or equal to

[15]% RTP, is low enough that these "windows," when the primary containment is not inerted, are also justified. The [24] hour time period is a reasonable amount of time to allow plant personnel to perform inerting or de-inerting.