ML18360A478

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Attachment 10: HEP Evaluation Related to Shutdown Cooling Isolation
ML18360A478
Person / Time
Site: Clinton Constellation icon.png
Issue date: 12/14/2018
From:
Exelon Generation Co
To:
NRC/RGN-III, Office of Nuclear Reactor Regulation
Shared Package
ML18360A500 List:
References
RS-18-146
Download: ML18360A478 (4)


Text

{{#Wiki_filter:ATTACHMENT 10 HEP Evaluation Related to Shutdown Cooling Isolation 1RHOPRPRVSDP-H--, OPERA TOR FAILS TO /SOLA TE PRVs - EDG 1B OUTAGESDP

    • Prlant _ 1?i1e:sfi~* _ Rec.o:i,d,_Date__

Clinton HEP.J Sumrharv Failure Probabilitv Total HEP Diagnosis 2.02E-03 Action 2.00E-02 2.20E-02 R:i~k: sr nificant O.OOE+OO O.OOE+OO N/A Plant I Initiating Event I __ TiminJ:i Analvsii:V - - -- Time available for cognition and recovery 180 Minutes Time available for recoverv 180 Minutes SPAR-H Available time (cognitive) 180 Minutes SPAR-H Available time (execution) ratio 2.2 Minutes EPRI Minimum level of dependence for recovery ZD

"'         ---                . ;                      --                   --              --           '*-*-      ..        ,. ._, ~- - -

Notes ",.(:... Time Available: 6 hours (GOTHIC plots are based on 6 hour response, but actual time available, also per GOTHIC, is closer to 9 before PRVs may be challenged). Tdelay - 1/2 hour for going through procedures (if Tdelay is increased, Tsw should also be increased) Texe - 2.5 hours - need RP brief (1/2 hour) plus transit time (1/2 hour) (steam tunnel, security checkpoint, not hot during shutdown, need clothing, flashlight, etc.), plus closing valve. Texe remains the same regardless of Tdelay. Texe x 2 =5 hours; Tsw =6 or more hours. Thus, Tsw > 2x Texe (and is !::ireater than 30 minutes) Select "Extra" time in Coqnitive for conservatism. '- - - PART. l,,OIAGNOSIS- -. PSFs PSF Levels Multiplier for DiaJ:inosis Available Time (recommended choice lnadeq_uate Time P(failure)

                                                                                                                             = 1.0--

based-on timing information in bold) Barely adequate time (-2/3 x 10 nominal) - Nominal time 1 Extra time (between 1 and 2 x X 0.1 nominal and> than 30 min) Expansive time (> 2 x nominal 0.01 and> 30 min) Insufficient information 1 Page 1

ATTACHMENT 10 HEP Evaluation Related to Shutdown Cooling Isolation Stress Extreme 5 Assume NRC's Choice Letter level High X 2 Nominal 1 Insufficient information 1 Complexity Highly complex 5 Moderately complex 2 Portable light, otherwise straightforward Nominal X 1 Obvious diagnosis 0.1 Insufficient information 1 Experience/Training Low 10 Operators have performed before Nominal X 1 High 0.5 Insufficient information 1 Procedures Not available 50 Incomplete 20 Available, but poor 5 Exist Nominal X 1 Diagnostic/symptom oriented 0.5 Insufficient information 1 Ergonomics/HM! Missing/Misleading 50 Poor 10 Nominal for diagnosis Nominal X 1 Good 0.5 Insufficient information 1 Fitness for Dutv Unfit P(failure) = 1.0 Degraded Fitness 5 Nominal X 1 Insufficient information 1 Work Processes Poor 2 Nominal X 1 Good 0.8 Insufficient information 1 D.iagnosis HEP 2.02E-03 P.ART II. ACTION. -- -- - - PSFs PSF Levels Multiplier for Diagnosis Available Time (recommended choice based Inadequate Time P(failure) = 1.0 on timing information in bold) Time available is about 10 the time Margin exists Nominal time X 1 Time available >= 5x the 0.1 time Time available is >= 50x 0.01 the time Insufficient Information 1 Stress/Stress ors Extreme 5 Assume NRC's Choice Letter level Hiqh X 2 Nominal 1 Insufficient Information 1 Page 2

ATTACHMENT 10 HEP Evaluation Related to Shutdown Cooling Isolation Complexity HiQhlv complex 5 Moderately complex 2 Does not change just because there is SBO Nominal X 1 Insufficient Information 1 Experience/Training Low 3 Operators have performed before Nominal X 1 HiQh 0.5 Insufficient Information 1 Procedures Not available 50 Incomplete 20 Available, but poor 5 Exist Nominal X 1 Insufficient Information 1 Ergonomics/HM! MissinQ/MisleadinQ 50 Assume ooor due to entering steam tunnel Poor X 10 Nominal 1 Good 0.5 Insufficient Information 1 Fitness for Duty Unfit P(failure) = 1.0 Degraded Fitness 5 Nominal X 1 Insufficient Information 1 Work Processes Poor 5 Nominal X 1 Good 0.5 Insufficient Information 1

Action. Probability 2.001::-02 PART Ill. DEPl;NDEN.CY Crew N/A Time N/A Location N/A Cues N/A Dependency Level Zero Diagnosis 2.02E-03 Total 2.20E-02 Page 3

HEP Evaluation Re~~J:; 10 0H:h~~Jown . Coolmg Isolation level al T1111e I Dep!alleacy I no addtional same Camplele 1 addtional doseintme Qmnro[Jl'&(le no addtional liffenn I Higll 1 addtional same Higll no addtional same Higll ootdose

                                       -l addtional              Madella no addtional liffenn                                Mudaa l adlMional             Lall' no addtional same                                   Madella
                                        ~ adlMional doseintme                                              Mudaa

- no addtional

                         ~dffen!d                                Mudaa
                                        -{ adlMional liffenn                                                         Mudaa no addtional same                              -    Lall'
                                         ~ adlMional ootdose no addtional
                                                             -   Lall' dffen!d                            -   Lall' l adlMional -      -
 .zero Page4}}