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Record of Review-Dispositions to Catawba Nuclear Station (CNS) PRA Facts and Obervations (F&Os)
	ML16105A451
Person / Time
Site:	Catawba
Issue date:	04/20/2016
From:	Stephen Dinsmore; NRC/NRR/DRA
To:	;
	Stephen Dinsmore, NRR/DRA 415-8482
References
	Download: ML16105A451 (13)
	v • d • e

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE AS-01 DA-C16 A SY-A10 AS-04 AS-A1 C AS-A2 AS-A7 AS-A10 QU-B6 AS-07 AS-A2 A AS-A7 AS-A10 AS-B1 AS-B5 QU-B6 SC-A3 SC-A4 SY-B5 DA-01 DA-B1 A DA-B2 DA-C2 DA-E1 DA-E2 DA-02 DA-A1 See PRA RAI 02.f.e in SE DA-A4 Section 3.4.2.1 regarding DA-C1 updating generic failure DA-C2 rate data.

DA-C9 DA-05 DA-A1 A DA-C2 DA-C14 DA-C16 DA-06 DA-A1 C DA-A4 DA-C1 DA-C2 DA-C9 DA-D3 DA-E1 DA-E2 DA-08 DA-D1 A DE-01 SY-C2 C DE-04 AS-B1 See response to PRA RAI 02.a (March 30, 2015 AS-B3 RAI responses) regarding loss of HVAC).

SY-A10 Acceptable to the NRC staff because the licensee SY-B5 states that room heatup calculations were performed and a loss of HVAC for the switchgear rooms, battery rooms, and control room was determined to have no impact on the risk results during the 24-hour mission time of the PRA.

HR-02 HR-B1 C HR-B2 HR-D1 HR-D2 1

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE HR-D4 HR-04 HR-E1 A HR-E2 HR-E3 HR-E4 HR-F1 HR-F2 HR-G4 HR-G5 HR-H1 HR-H2 HR-05 HR-E1 C HR-E2 HR-E3 HR-F2 HR-G1 HR-G3 HR-H1 HR-H2 SC-A2 SC-A6 SC-B3 SC-C1 SC-C2 HR-09 HR-G5 C IE-03 IE-Al A IE-A5 IE-A6 IE-A9 IE-04 IE-C12 A DA-C16 IE-06 AS-B1 See response to PRA RAI 02.a (March 30, 2015 IE-A2 RAI responses) regarding loss of HVAC).

IE-C6 Acceptable to the NRC staff because the licensee states that room heatup calculations were performed and a loss of HVAC for the switchgear rooms, battery rooms, and control room was determined to have no impact on the risk results during the 24-hour mission time of the PRA.

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Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE IE-08 IE-C9 See response to PRA RAI 2.f.a (January 28, 2015 IE-C10 RAI responses) regarding treatment of common cause failure in the development of the frequency for loss of service water. Acceptable to the NRC staff because the licensee states that the loss of service water frequency was developed consistent with the guidance in EPRI TR 1016741, Support System Initiating Events: Identification and Quantification Guideline (December 2008).

IFPP-A2-01 IFPP-A2 See response to PRA RAI 02.f.b (January 28, 2015 RAI responses) regarding disposition to internal flooding F&Os. Acceptable to the NRC staff because the licensee states that the modeling changes made to address the internal flooding F&Os were incorporated in the PRA model used to generate the risk results reported in the LAR.

IFSN-A10-01 IFSN-A10 See response to PRA RAI 02.f.b (January 28, 2015 RAI responses) regarding disposition to internal flooding F&Os. Acceptable to the NRC staff because the licensee states that the modeling changes made to address the internal flooding F&Os were incorporated in the PRA model used to generate the risk results reported in the LAR.

IFSN-A7-01 IFSN-A7 See response to PRA RAI 02.f.b (January 28, 2015 RAI responses) regarding disposition to internal flooding F&Os. Acceptable to the NRC 3

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE staff because the licensee states that the modeling changes made to address the internal flooding F&Os were incorporated in the PRA model used to generate the risk results reported in the LAR.

IFSN-B1-01 IFSO-B1 A IFSN-B1 IFEV-B1 IFSO-A 1-01 IFSO-A1 See response to PRA RAI 02.f.b (January 28, IFEV-A5 2015 RAI responses) regarding disposition to IFSN-A10 internal flooding F&Os. Acceptable to the NRC staff because the licensee states that the modeling changes made to address the internal flooding F&Os were incorporated in the PRA model used to generate the risk results reported in the LAR.

IFSO-A2-01 IFSO-A2 A IFSN-A11 IFEV-A4 IFSO-A5-01 IFSO-A5 A IFSO-A6-01 IFPP-A5 C IFSO-A6 IFSO-B3-01 IFPP-B3 C IFSO-B3 2012 Focused- LE-B2 A scope Peer LE-C1 Review LE-C3 LE-C4 LE-C9 LE-C11 LE-D2 LE-D3 LE-D6 LE-E2-01 LE-E2 C LE-G3-01 LE-F1 C LE-G3 LE-G6-01 LE-G6 C LAR DA-C8 C LAR DA-C9 C LAR DA-C11 C DA-C12 DA-C13 LAR DA-D3 C LAR DA-D4 C LAR DA-D5 C 4

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE LAR DA-D6 C LAR DA-E3 C 2008 Self- IE-A8 C assessment 2008 Self- IE-B2 C assessment LAR IE-C14 C See response to PRA RAI 02.f.c (January 28, 2015 RAI responses) regarding crediting of motor operated valves (MOVs) under differential pressure conditions. Acceptable to the NRC staff because the licensee states that crediting these MOVs has an insignificant impact to the PRA results reported in the LAR.

LAR QU-E4 C LAR QU-F6 C LAR SY-A11 A 2008 Self- SY-A15 C assessment 2008 Self- SY-A4 C assessment QU-01 QU-B2 A QU-B3 QU-02 AS-B5 A QU-A4 QU-C1 QU-C2 SC-A3 SC-A4 SY-B5 QU-04 QU-F2 A QU-05 HR-G6 See response to PRA RAI 02.b (January 28, 2015 QU-A5 RAI responses) regarding post-initiator human DA-C16 error probability quantification. Acceptable to the NRC staff because the licensee states that a consistency check of the post-initiator human error probability quantifications have been completed with no changes to the PRA model.

QU-08 QU-A5 A QU-B7 QU-B8 QU-12 QU-A2 See response to PRA RAI 02.f.d (January 28, QU-A4 2015 RAI responses) regarding the conditional QU-D4 core damage probabilities (CCDPs) for small loss QU-D6 of coolant accident (LOCA), steam generator tube rupture (SGTR), loss of instrument air, and 5

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE inadvertent safety injection system (SS) actuation. Acceptable to the NRC staff because the licensee explains the reason for the differences between the small LOCA and SGTR initiating events CCDPs, and explains that the CCDPs for the loss of instrument air and inadvertent SS actuation initiating events is coincidental.

SY-03 SC-A3 See response to PRA RAI 02.c (January 28, 2015 SC-B1 RAI responses) regarding the the impact on the SC-C1 PRA results of the new success criteria.

SC-C2 Acceptable to the NRC staff because the licensee SY-B7 states that the success criteria applied in the LAR SY-C1 PRA model are bounding of the new success SY-C2 criteria or the new success criteria did not result SY-A10 in a change to the PRA model.

SY-A13 SY-A18 SY-A21 AS-A3 SY-04 SY-A13 See response to PRA RAI 02.e (January 28, 2015 SY-A22 RAI responses) regarding excluding the failure to isolate the Non-Essential Reactor Building Header from the PRA model. Acceptable to the NRC staff because the licensee states that the MSO evaluation performed for the Fire PRA was performed consistent with the guidance in NEI 00-01 to evaluate plant-specific MSO considerations, which included evaluating many scenarios not originally included in the Internal Events PRA.

SY-06 AS-B3 A SY-A18 SY-A21 SY-A22 SY-B14 TH-01 SC-A2 See response to PRA RAI 02.c (January 28, 2015 SC-B1 RAI responses) regarding the the impact on the SC-B3 PRA results of the new success criteria.

SC-B4 Acceptable to the NRC staff because the licensee SC-B5 states that the success criteria applied in the LAR SY-B7 PRA model are bounding of the new success criteria or the new success criteria did not result in a change to the PRA model. Also see response to PRA RAI 02.d (January 13, 2015 RAI responses) regarding the meaning of negligible impact. Acceptable to the NRC staff because the licensee states that there is no impact on the PRA results if core damage is defined as 2000 degrees F because there is no change in the success criteria and a new plant-specific HRA timing 6

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE analysis showed that the HRA timing used in the Fire PRA supported the HEPs used in the PRA.

TH-02 AS-A8 See response to PRA RAI 2.d (January 13, 2015 SC-A1 RAI responses) regarding the meaning of SC-A2 negligible impact. Acceptable to the NRC staff because the licensee states that there is no impact on the PRA results if core damage is defined as 2000 degrees F because there is no change in the success criteria and a new plant-specific HRA timing analysis showed that the HRA timing used in the Fire PRA supported the HEPs used in the PRA.

TH-03 AS-A3 See response to PRA RAI 02.c (January 28, 2015 AS-A5 RAI responses) regarding the the impact on the AS-A9 PRA results of the new success criteria.

SC-A2 Acceptable to the NRC staff because the licensee SC-A3 states that the success criteria applied in the LAR SC-A6 PRA model are bounding of the new success SC-B1 criteria or the new success criteria did not result in SC-B2 a change to the PRA model.

SC-B3 SC-B4 SC-C1 SC-C2 SY-A10 SY-A13 SY-A18 SY-A21 SY-B7 TH-05 HR-F2 See response to PRA RAI 02.c (January 28, 2015 HR-G4 RAI responses) regarding the the impact on the SC-A2 PRA results of the new success criteria.

SC-A3 Acceptable to the NRC staff because the licensee SC-A6 states that the success criteria applied in the LAR SC-B3 PRA model are bounding of the new success SC-B5 criteria or the new success criteria did not result SC-C1 in a change to the PRA model.

SC-C2 TH-06 AS-B3 See response to PRA RAI 02.a (March 30, 2015 SY-B7 RAI responses) regarding loss of HVAC).

SY-B8 Acceptable to the NRC staff because the licensee SY-A18 states that room heatup calculations were performed SY-A21 and a loss of HVAC for the switchgear rooms, 7

Record of Review Dispositions to Catawba Nuclear Station (CNS) Internal Events PRA Facts and Observations (F&Os)

ACCEPTABLE TO STAFF VIA Finding ID (F&O) or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O ID SR (A/B/C) Not Discussed in the SE Discussed in the SE SY-A22 battery rooms, and control room was determined to SC-A3 have no impact on the risk results during the 24-SC-A6 hour mission time of the PRA.

SC-B2 SC-B5 SC-C1 SC-C2 A: The NRC staff finds that the licensees disposition for the capability category of the SR as described by the licensee in the LAR provides confidence that the requirements of the SR have been addressed and, if needed, the PRA has been modified, and therefore the PRA quality with respect to the SR is acceptable for this application. Examples of acceptable CC-I SRs are modeling methods that yield conservative FRE and change evaluation results.

B: The NRC staff finds that the licensees disposition of the capability category of the SR as described by the licensee in the LAR and further clarified during the audit provides confidence that requirements of the SR have been addressed and, if needed, the PRA has been modified, and therefore the PRA quality with respect to the SR is acceptable for this application. Examples of acceptable CC-I SRs are modeling methods that yield conservative FRE and change evaluation results.

C: The NRC staff finds that the licensees disposition for the capability category of the SR, as described by the licensee in the LAR, would have a negligible effect on the evaluations relied upon to support fire risk evaluations and has no impact on the conclusions of the risk assessment and therefore the PRA quality with respect to the SR is acceptable for this application. Examples are those SRs that don't affect the fire PRA.

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Record of Review Dispositions to Catawba Nuclear Station (CNS) Fire PRA Facts and Observations (F&Os)

Finding/Suggestion ACEPTABLE TO STAFF VIA (F&O) ID or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O SR Not Discussed in the SE Discussed in the SE (A/B/C)

CS-A11-01 CS-A11 A CS-B1-01 CS-B1 A ES-C1-01 ES-C1 A ES-C2-01 ES-C2 A FQ-A2-01 FQ-A2 A FQ-F1-01 FQ-F1 C FQ-F1-02 FQ-F1 B FSS-A1-01 FSS-A1 A See response to PRA RAI 01.a (February 27, 2015) regarding screening of non-propagating fixed and transient ignition sources.

Acceptable to the NRC staff because the licensee states that fixed ignition sources excluded from quantification of the Fire PRA model were done consistent with the criteria in Section 8.5.3 of NUREG/CR-6850 and that the only instances where the non-severe potion of a fire scenario was excluded involved components that were not credited in the Fire PRA.

The licensee also stated that the Fire PRA documentation will be updated accordingly.

FSS-A2-01 FSS-A2 A FSS-H10-01 FSS-H10 A HRA-A2-01 HRA-A2 See PRA RAI 12 and 12.01 in SE Section 3.4.4 regarding identification and classification of abandonment actions.

HRA-A4-01 HRA-A4 See response to PRA RAI 01.b.iv (January 28, 2015 RAI responses) regarding talk throughs.

Acceptable to the NRC staff because the licensee states that all operator actions with risk 9

Record of Review Dispositions to Catawba Nuclear Station (CNS) Fire PRA Facts and Observations (F&Os)

Finding/Suggestion ACEPTABLE TO STAFF VIA (F&O) ID or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O SR Not Discussed in the SE Discussed in the SE (A/B/C) achievement worth greater than 1.02 or which were considered risk significant actions were reviewed with operators, and additional operator actions credited in the Fire PRA were also talked through with operators.

HRA-B3-01 HRA-B3 See response to PRA RAI 01.c.iii See PRA RAI 01.b.i and ii (January 28, 2015 RAI responses) in SE Section 3.4.2.2 regarding use of JHEPs less than regarding updating HEPs 1E-05. Acceptable to the NRC staff using the NUREG-1921 because the licensee identified that methodology.

the fire PRA applies several JHEPs less than 1E-05 and justifies the lower JHEPs based on 1) large time window between actions, 2) actions are taken based on different cues, and 3) there are intervening successes between some of the actions.

HRA-C1-02 HRA-C1 A HRA-D2-01 HRA-H2 See response to PRA RAI 01.c (January 28, 2015 RAI responses) regarding crediting non-proceduralized operator actions.

Acceptable to the NRC staff because the licensee identifies just one additional action beyond that identified by the peer review and determined that it does not impact the risk results.

PRM-B2-01 PRM-B2 See NRC Staff Evaluation in IEPRA Record of Review PRM-B5-01 PRM-B5 A PRM-B6-01 PRM-B6 See response to PRA RAI 01.c (January 28, 2015 RAI responses) regarding crediting non-proceduralized operator actions.

Acceptable to the NRC staff 10

Record of Review Dispositions to Catawba Nuclear Station (CNS) Fire PRA Facts and Observations (F&Os)

Finding/Suggestion ACEPTABLE TO STAFF VIA (F&O) ID or Supporting Requirement (SR) Review of RAI Response Plant Disposition F&O SR Not Discussed in the SE Discussed in the SE (A/B/C) because the licensee identifies just one additional action beyond that identified by the peer review and determined that it does not impact the risk results.

PRM-B7-01 PRM-B7 B PRM-B11 PRM-B11 See responses to PRA RAIs 01.b (no F&O) and 01.c discussed previously in this table (i.e., F&Os HRA-A4-01, HRA-B4-01, HRA-D2-01, PRM-B6-01)

SF-A3-01 SF-A3 A SF-A5-01 SF-A5 A A: The NRC staff finds that the disposition of the F&O as described by the licensee in the LAR provides confidence that the issues raised by the F&O have been addressed and, if needed, the PRA has been modified, and therefore the resolution of the F&O is acceptable for this application.

B: The NRC staff finds that the disposition of the F&O as described by the licensee in the LAR and further clarified during the audit provides confidence that the issues raised by the F&O have been addressed and, if needed, the PRA has been modified, and therefore the resolution of the F&O is acceptable for this application.

C: The NRC staff finds that the resolution of the F&O, as described by the licensee in the LAR, would have a negligible effect on the evaluations relied upon to support fire risk evaluations and has no impact on the conclusions of the risk assessment and therefore the resolution of the F&O is acceptable for this application. Examples of such F&Os may be suggestions, as well as those F&Os that don't affect the fire PRA. Documentation issues may fall into this category as well.

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Record of Review Dispositions to Supporting Requirements (SRs) for CNS Fire PRA Met at Capability Category I ACEPTABLE TO STAFF VIA Supporting Review of RAI Response Requirement F&O ID Plant (SR) Disposition Not Discussed in the SE Discussed in the SE (A/B/C)

PP-B3 PRM-B3-01 A PP-B5 PRM-B5-01 A CS-B1 CS-B1-01 A FSS-B2 FSS-B2-01 See PRA RAI 11 and 11.01 in SE Section 3.4.2.2 regarding the MCR abandonment analysis.

FSS-C1 FSS-C1-01 A FSS-C2 FSS-C2-01 A FSS-C3 FSS-C3-01 A FSS-F2 FSS-F2-01 A FSS-F3 FSS-F3-01 A FSS-G4 FSS-G4-01 A FSS-H2 FSS-H2-01 A HRA-A3 ES-C2-01 A HRA-A4 HRA-A4-01 See response to PRA RAI 01.b.iv (January 28, 2015 RAI responses) regarding talk throughs. Acceptable to the NRC staff because the licensee states that all operator actions with risk achievement worth greater than 1.02 or which were considered risk significant actions were reviewed with operators, and additional operator actions credited in the Fire PRA were also talked through with operators.

HRA-B4 ES-C1-01 A HRA-C1 HRA-C1-02 See PRA RAI 01.b.i and ii in SE Section 3.4.2.2 regarding updating HEPs 12

Record of Review Dispositions to Supporting Requirements (SRs) for CNS Fire PRA Met at Capability Category I ACEPTABLE TO STAFF VIA Supporting Review of RAI Response Requirement F&O ID Plant (SR) Disposition Not Discussed in the SE Discussed in the SE (A/B/C) using the NUREG-1921 methodology.

HRA-D1 PRM-B6-01 See PRA RAI 01.b.i and ii in SE Section 3.4.2.2 regarding updating HEPs using the NUREG-1921 methodology.

A: The NRC staff finds that the licensees disposition for the capability category of the SR as described by the licensee in the LAR provides confidence that the requirements of the SR have been addressed and, if needed, the PRA has been modified, and therefore the PRA quality with respect to the SR is acceptable for this application. Examples of acceptable CC-I SRs are modeling methods that yield conservative FRE and change evaluation results.

B: The NRC staff finds that the licensees disposition of the capability category of the SR as described by the licensee in the LAR and further clarified during the audit provides confidence that requirements of the SR have been addressed and, if needed, the PRA has been modified, and therefore the PRA quality with respect to the SR is acceptable for this application. Examples of acceptable CC-I SRs are modeling methods that yield conservative FRE and change evaluation results.

C: The NRC staff finds that the licensees disposition for the capability category of the SR, as described by the licensee in the LAR, would have a negligible effect on the evaluations relied upon to support fire risk evaluations and has no impact on the conclusions of the risk assessment and therefore the PRA quality with respect to the SR is acceptable for this application. Examples are those SRs that don't affect the fire PRA.

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