ML18360A478
| ML18360A478 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| 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 1 RHOPRPRVSDP-H--, OPERA TOR FAILS TO /SOLA TE PRVs - EDG 1 B 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:;0H:h~~J 10 own Coolmg Isolation T1111e I level al I Dep!alleacy no addtional same doseintme 1 addtional same liffenn no addtional I 1 addtional same no addtional ootdose -l addtional liffenn no addtional l adlMional same no addtional doseintme ~ adlMional liffenn ~dffen!d no addtional -{ adlMional same no addtional ootdose ~ adlMional dffen!d no addtional l adlMional Camplele Qmnro[Jl'&(le Higll Higll Higll Madella Mudaa Lall' Madella Mudaa Mudaa Mudaa Lall' Lall' Lall' .zero Page4}}