ML040410647
ML040410647 | |
Person / Time | |
---|---|
Site: | South Texas ![]() |
Issue date: | 01/21/2004 |
From: | South Texas |
To: | Office of Nuclear Reactor Regulation |
Webb M, NRR/DLPM, 415-1347 | |
Shared Package | |
ml040560491 | List: |
References | |
Download: ML040410647 (16) | |
Text
STP Risk-Informed Technical S pecifications Application Meeting with NRC January 21, 2004 Enclosure 3
Introduction
- STP Participants
- Rick Grantom Risk Management Manager
- Drew Richards Applications Development Lead
-Wayne Harrison Licensing Engineer 1/19/04 2
Desired Outcom es
- Identify the primary issues with STP proposed Risk-informed TS (RITS) and agree on a process for their resolution
- Scope of affected TS
- Exceptions to Risk Managed TS guidance
- Level of detail required for NRC review
- PRA and deterministic analyses to be reviewed
- Configuration Risk Management Program (CRMP) 1/19/04 3
Proposed Agenda
- Submittal schedule
- Implementation example Standby Diesel Generator (SDG) 113 day extended allowed outage time
- Level of detail required for NRC review 1/19/04 4
Submittal Schedule
- Submitted "Letter of Intent" with proposed changes in early 2003
- Driver and basis for this meeting
- Identify and resolve policy issues
- Propose STP as a pilot
- Provides opportunity for industry involvement
- Formal License Amendment submittal 90 days after major issues are resolved
- Final approval in mid to late 2004 1/19/04 5
Scope and Content
- Selected instrumentation of TS
- MFIVs 3.3
- Atmospheric Steam Relief
- Code safety valves
- Component Cooling Water
- Pressurizer PORVs
- Essential Cooling Water
- FHBHVAC
- RHR
- Essential Chilled Water
- SDGs and Off-site circuits
- RCB Purge
- Batteries
- ESF Buses
- Containment Fan Coolers
- MSIVs 1/19/04 6
Exceptions to Guide
- Comparison to "Standard RITS" References the Implementation Guidelines Takes exception to proscription against allowing loss of function Would apply to conditions where TS 3.0.3 currently applies.
TS 3.13 format is different, but the application is the same 1/19/04 7
Draft TS 3.13 RISK MANAGEMENT ALLOWED OUTAGE TIME DETERMINATIONS LIMITING CONDITION FOR OPERATION 3.13.1 When referred to this specification, equipment that has been removed from service or declared inoperable shall be evaluated for its impact on plant risk and allowed outage times determined accordingly.
APPLICABILITY: As required by the referencing specification ACTION:
Determine that the configuration is acceptable for Completion Time extension beyond the [Front Stop AOT],
AND Determine that the configuration is acceptable for continued operation beyond the [Front Stop AOT] whenever configuration changes occur that may affect plant risk, AND Restore required inoperable [subsystem, component] to OPERABLE status within the Acceptable Allowed Outage Time Extension or 30 days, whichever is shorter.
OR Take the ACTION required in the referencing specification for required action or completion time not met SURVEILLANCE REQUIREMENTS 4.13.1: As required by the referencing specification 1/19/04 8
Sample Specification PLANT SYSTEMS 3/4.7.4 ESSENTIAL COOLING WATER SYSTEM LIMITING CONDITION FOR OPERATION 3.7.4 At least three independent essential cooling water loops shall be OPERABLE.
APPLICABILITY: MODES 1, 2, 3, and 4.
ACTION:
- a. With only two essential cooling water loops OPERABLE, within 7 days restore at least three loops to OPERABLE status or apply the requirements of Specification 3.13, OR be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- b. With two or more essential cooling water loops inoperable, within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> restore at least two loops to OPERABLE status or apply the requirements of Specification 3.13, OR be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
1/19/04 9
Level of Detail Needed for NRC Review
- Table 2 of STP application addresses each proposed change Deterministic and risk basis for each change
- Implementation Configuration Risk Management Procedure 1/19/04 10
Application of RITS Example 1: Routine Train A work week with emergent Train B condition Time Event Frontstop Calculated Risk Comment (hh:mm) AOT (/hr)
(time to reach 1E-05) 00:00 Begin Train A work HHSI (3.5.2.a): 7 days NA, planned 5.9E-09 Routine planned maintenance week (SDG, ECW, CCW (3.7..3.a): 7 days to remain CCW, HHSI) ECW (3.7.4.a): 7 days within SDG (3.8. .1.b): 14 days frontstop allowed outage time.
24:00 Train B HHSI found 3.5.2.b: 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to apply TS 24 days 1.7E-08 Emergent condition where CTS would to be inoperable 3.13 require TS 3.0.3 entry. RITS permits the station to address the condition with normal work controls.
36:00 Train B HHSI Exit TS 3.5.2.b and TS 3.13 NA 5.9E-09 restored applicability.
Back on the work week clock with 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> elapsed.
1/19/04 11
Application of RITS Example 2: Emergent condition while in configuration where TS 3.13 is in use Time Event Frontstop Calculated Risk Comment (hh:mm) AOT (/hr)
(time to reach IE-05 00:00 ECW pump TS 3.7.4.a: 7 days 1 train of 4.5E-09 TS 3.13 requirements apply after 7 days.
replacement (Also makes associated ECW could The risk is calculated from the time the expected to last 10 SDG inoperable) be allowed ECW is taken out of service.
days. OOS up to the 30-day backstop 8 days Turbine-driven TS 3.7.1 .2.b: 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> 27 days 1.5E-08 Regardless of the frontstop time for the AFW found to be TS 3.8. 1.1 .d: 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> TDAFW pump, TS 3.13 applies because inoperable the ECW has gone beyond its frontstop.
TS 3.13 requires a determination of the acceptability of the configuration with the additional inoperable TDAFW.
Application of the CRMP would determine the configuration is acceptable.
9 days ECW pump is TS 3.7.1.2.b: 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> less > 30 days 1.5E-09 The condition that caused TS 3.13 to restored the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that have (backstop apply has been exited and there are no TS transpired. would apply) beyond their frontstop time. The frontstop AOT may be applied to the TDAFW.
1/19/04 12
Application of RITS Example 3: Same as Example 2, except that the emergent condition is restored first Time Event Frontstop Calculated Risk Comment (hh:mm) AOT (/hr)
(time to reach IE-05) 00:00 ECW pump TS 3.7.4.a: 7 days 1 train of 4.5E-09 TS 3.13 requirements apply after 7 days.
replacement ECW could The risk is calculated from the time the expected to last 10 be allowed ECW is taken out of service days. OOS up to the 30-day backstop 8 days Turbine-driven TS 3.7.1 .2.b: 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> 27 days 1.5E-08 Regardless of the frontstop time for the AFW found to be TS 3.8.1.l.d: 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> TDAFW pump, TS 3.13 applies because inoperable the ECW has gone beyond its frontstop.
TS 3.13 requires a determination of the acceptability of the configuration with the additional inoperable TDAFW.
Application of the CRMP would determine the configuration is acceptable.
9 days TD AFW restored NA > 30 days 4.5E-09 TS 3.13 still applies. TDAFW no longer contributes to risk calculation. A new completion time may be calculated.
1/19/04 13
SDG 22 13 Day Extended AOT
- One-time emergency TS Change approved on December 30, 2003
- Configuration risk to be managed by application of the STP Configuration Risk Management Program (CRMP).
- Good example of how the CRMP works
- Duration and risk bound any that would be encountered using proposed RITS 1/19/04 14
SDG 22 113 Day Extended AOT
- Installed non-safety DGs (NDG) as compensatory action
- RG criteria met without credit for NDGs
- STPNOC is closely monitoring the risk profile 1/19/04 15
SDG 22 113 Day Extended AOT Comparison of Planned and Actual Ri" ICCDP) for Unit 2 During SDG 22 Outage ChAA Soutto; Nt: Pl~irWbd - RA Rov4 Ihkdal fimelud~ NDG etfbet ntIsk (ND fW 0hdJ,*6M4Isoad Ottl d* com sikuoX Rev 4 Pianned PRA Rtv 4 Made assUrif no NDG efflct en risk AcIja53I RMtCAL dati, fr prewout woc wee& and PRA Rev 4 0 A A 51 W X c c: 2) N > 23 Ba a , > t £ g i=> 8 -- ~~~~~~~~~~~ ;.0 j- - jDG' kain'ed - i 4 kitiM I 1/19/04 16