ML19056A424
| ML19056A424 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force |
| Issue date: | 02/21/2019 |
| From: | Michelle Honcharik NRC/NRR/DSS/STSB |
| To: | |
| Honcharik M, NRR/DSS, 301-415-1774 | |
| Shared Package | |
| ML19056A435 | List: |
| References | |
| Download: ML19056A424 (9) | |
Text
Technical Specifications Task Force A Joint Owners Group Activity TSTF 1
Proposed Path Forward on TSTF-568, "Clarify Applicability of BWR/4 TS 3.6.2.5 and TS 3.6.3.2"
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Background
- TSTF-568, Rev. 0, "Clarify Applicability of BWR/4 TS 3.6.2.5 and TS 3.6.3.2,"
- Applicable to BWR plants with Mark I and Mark II containments (BWR/2, /3, /4, and /5 plants)
- Submitted December 19, 2017
- NRC issued acceptance letter and review schedule on March 8, 2018 2
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Status
- At the August 9, 2018 TSTF/NRC public meeting, the NRC stated that they support the change to TS 3.6.2.5, Drywell-to-Suppression Chamber Differential Pressure
- Only applicable to three BWR plants (Dresden, Fitzpatrick, and Quad Cities) 3
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Status
- NRC stated they cannot support the change to TS 3.6.3.2, Primary Containment Oxygen Concentration
- Applicable to all BWR/2, BWR/3, BWR/4, and BWR/5 units
- The NRC does not agree with the existing justification of "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."
- While the risk to the public is too small to warrant a backfit on the issue, the NRC staff is not comfortable with issuing a change to the TS that relies on that justification.
- The TSTF was unable to find supporting analysis for the statement and accepts the NRC position.
4
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Proposed Revision
- The TSTF has revised the traveler to address the staff concerns:
- Revise the TS 3.6.2.5, "Drywell-to-Suppression Chamber Differential Pressure," Applicability to Mode 1 with thermal power > [15]%
- Supported by the analysis referenced in TSTF-568.
- Revise the TS 3.6.3.2, "Primary Containment Oxygen Concentration," Applicability to Mode 1.
- Addresses the NRC staff concern.
- TS 3.6.3.2 Required Action B.1 is revised to require being in Mode 2 in 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 5
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Proposed Revision
- For both TS:
- The existing Applicability exceptions are eliminated.
- Required Action A.1 (restore the value to within limit) is changed from 8 and 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
- A Note is applied to Required Action A.1 permitting the use of LCO 3.0.4.c to enter the Applicability with the LCO not met.
- The Required Action A.1 and the Note will be used instead of the existing Applicability exceptions to permit entering the Applicability with the limit not met during a startup, and to enter the action prior to exiting the Applicability on a shutdown
- The Bases will state that entering Required Action A.1 prior to a shutdown without intention to restore compliance prior to exiting the Applicability is acceptable in this case.
6
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Proposed Revision
- The Required Action A.1 Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is based on:
- The time to perform on-line maintenance at low power (typically
< 15% RTP) requiring primary containment or suppression pool entry.
- De-inert the primary containment and suppression pool while reducing power to permit containment entry (24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />)
(existing allowance),
- Perform on-line maintenance in containment (24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />), and
- Re-inert the primary containment and suppression pool while increasing to full power (24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) (existing allowance).
- The low probability of an event that would generate significant hydrogen and require primary containment to be inert.
7
Technical Specifications Task Force A Joint Owners Group Activity TSTF 8
Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-568 Proposed Revision Discussion 9