ML021980258: Difference between revisions

From kanterella
Jump to navigation Jump to search
(StriderTol Bot insert)
 
(StriderTol Bot change)
 
Line 18: Line 18:


=Text=
=Text=
{{#Wiki_filter:}}
{{#Wiki_filter:July 17, 2002 MEMORANDUM TO: Richard Laufer, Chief Section I-2, Project Directorate I Division of Licensing and Project Management FROM:                      F. Mark Reinhart, Chief/RA/ Mark Caruso for/
Licensing Section Probabilistic Safety Assessment Branch Division of Systems Safety and Analysis
 
==SUBJECT:==
SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)
In response to your request, the Probabilistic Safety Assessment Branch (SPSB) in the Division of Systems Safety and Analysis (DSSA) has completed its review of the licensees basis for concluding that the small array valves that return service water coolant to the ultimate heat sink do not meet criterion 4 of 10CFR 50.36(2)(ii)(c)(D) for inclusion in technical specifications. Our input for the staff safety evaluation is attached.
In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, we accept the licensees conclusion that criterion 4 is not met for these valves, i.e.,
that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.
Docket Nos. 50-387, 50-388
 
==Attachment:==
 
Safety Evaluation CONTACT:        Mark Caruso, SPSB/DSSA 415-1310
 
July 17, 2002 MEMORANDUM TO: Richard Laufer, Chief Section I-2, Project Directorate I Division of Licensing and Project Management FROM:                        F. Mark Reinhart, Chief/RA/ Mark Caruso for/
Licensing Section Probabilistic Safety Assessment Branch Division of Systems Safety and Analysis
 
==SUBJECT:==
SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)
In response to your request, the Probabilistic Safety Assessment Branch (SPSB) in the Division of Systems Safety and Analysis (DSSA) has completed its review of the licensees basis for concluding that the small array valves that return service water coolant to the ultimate heat sink do not meet criterion 4 of 10CFR 50.36(2)(ii)(c)(D) for inclusion in technical specifications. Our input for the staff safety evaluation is attached.
In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, we accept the licensees conclusion that criterion 4 is not met for these valves, i.e.,
that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.
Docket Nos. 50-387, 50-388
 
==Attachment:==
Safety Evaluation DISTRIBUTION                SPSB R/F          MCaruso DOCUMENT NAME: G:\SPSB\caruso\susquehanna_crit4.wpd ACCESSION NO.:ML021980258                              TEMPLATE NO.NRR-096 To receive a copy of this document, indicate in the box C=Copy w/o attachment/enclosure E=Copy with attachment/enclosure N = No copy OFFICE    SPSB:DSSA                          SC:SPSB:DSSA NAME      MCaruso                            FMReinhart/c/M. Caruso for DATE      07/17/02                            07/ 17/02 OFFICIAL FILE COPY
 
SPSB COVER PAGE DOCUMENT:  G:\SPSB\caruso\susquehanna_crit4.wpd
 
==SUBJECT:==
SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)
ORIGINATOR M. Caruso, 415-1310 SECRETARY: Nasreen Hasan, 415-3229 DATE:              July 17, 2002
                             ROUTING LIST 
NAME              DATE
: 1. M.Caruso                  07/  /02
: 2. M. Reinhart              07/  /02
: 3.                            07/  /02
: 4.                            07/  /02
: 5.                            07/  /02
: 6. Secretary/Dispatcher      07/  /02 ADAMS ACCESSION #:ML0                          TEMPLATE #: NRR-096
 
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FACILITY OPERATING LICENSE NO NPF-14, NPF-22 PP&L Susquehanna LLC SUSQUEHANNA STEAM ELECTRIC STATION DOCKET NOS. 50-387, 50-388 1 INTRODUCTION By letter dated June 1, 2001, supplemented by a letter dated June 28, 2002, PPL Susquehanna, LLC (the licensee),
requested an amendment to Facility Operating License No. NPF-14 and NPF-22 for the Susquehanna Steam Electric Station. The proposed amendment would modify Technical Specification (TS) Surveillance Requirement SR 3.7.1 to add operability requirements and surveillance requirements for the Ultimate Heat Sink (UHS) spray bypass valves and large array valves. The proposed change also reduces the allowed completion times for the conditions applicable to the Residual Heat Removal Service Water (RHRSW) system. The proposed change does not add operability requirements and surveillance requirements for the UHS small array valves. The licensees rationale for not adding requirements for the small array valves is that the small array valves do not satisfy any of the criteria in 10CFR50.36 for inclusion of limiting conditions for operation in the Technical Specifications. This evaluation addresses the licensees assessment against Criterion 4 in 10CFR50.36, i.e.,
A structure, system or component which operating experience or probabilistic risk assessment has shown to be significant to public health and safety.
Licensee assessments against other criteria in 10CFR50.36 are addressed elsewhere.
2 EVALUATION In lieu of specific guidance for addressing Criterion 4 in 10CFR 50.36, the licensee has utilized assessments of safety significance made per the Maintenance Rule (i.e., 10CFR 50.65) for the UHS components as the basis for determining whether or not the components in question are significant to public health and safety. These assessments have been made using a risk ranking process based on a probabilistic risk assessment and insights from the licensees Maintenance Rule Expert Panel and Generic Letter 89-10 (Motor Operated Valves) Expert Panel.
Using the Maintenance Rule assessment program, the licensee classified the spray bypass valves and large spray array valves as High Safety Significant. These valves provide a redundant primary means of success for the Residual Heat Removal Service Water system and Emergency Service Water system. While the small array valves can provide a back-up success path under some conditions, the time requirement for these valves to operate is greater than four hours, which allows for manual actuation of these valves if either of the primary success paths cannot be recovered. These factors are significant contributors to the relatively low risk importance of the small Attachment
 
array valves which has driven the licensees significance determination for these valves to a non-risk significant classification.
The staff believes that in lieu of specific staff guidance for addressing Criterion 4 in 10CFR 50.36, use of the Maintenance Rule assessment process is an acceptable means of addressing criterion 4 of 10CFR 50.36 for the small array valves at Susquehanna Units 1 and 2 because (1) it utilizes probabilistic risk assessment and also allows for insights from operating experience to be brought to bear via the expert panel review process, and (2) the licensees assessment process was found to be adequate by the NRC in the Maintenance Rule Base Line Inspection Program (Inspection Report 50-387/98-04 & 50-388/98-04, dated July 16, 1998).
3 CONCLUSION In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, the staff accepts the licensees conclusion that criterion 4 is not met for these valves, i.e., that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.
Principal contributor:
Mark Caruso Attachment}}

Latest revision as of 12:37, 26 March 2020

Safety Evaluation Input for Proposed Changes to the Susquehanna, Units 1 & 2 Technical Specifications Implementing Operability Requirements for the Ultimate Heat Sink Spray Valves (TAC Nos. MB2119 & MB2120)
ML021980258
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 07/17/2002
From: Reinhart F
NRC/NRR/DSSA/SPSB
To: Richard Laufer
NRC/NRR/DLPM/LPD1
Caruso Mark , SPSB/DSSA/NRR, 415-1310
References
TAC MB2119, TAC MB2120
Download: ML021980258 (6)
v • d • e


Text

July 17, 2002 MEMORANDUM TO: Richard Laufer, Chief Section I-2, Project Directorate I Division of Licensing and Project Management FROM: F. Mark Reinhart, Chief/RA/ Mark Caruso for/

Licensing Section Probabilistic Safety Assessment Branch Division of Systems Safety and Analysis

SUBJECT:

SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)

In response to your request, the Probabilistic Safety Assessment Branch (SPSB) in the Division of Systems Safety and Analysis (DSSA) has completed its review of the licensees basis for concluding that the small array valves that return service water coolant to the ultimate heat sink do not meet criterion 4 of 10CFR 50.36(2)(ii)(c)(D) for inclusion in technical specifications. Our input for the staff safety evaluation is attached.

In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, we accept the licensees conclusion that criterion 4 is not met for these valves, i.e.,

that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.

Docket Nos. 50-387, 50-388

Attachment:

Safety Evaluation CONTACT: Mark Caruso, SPSB/DSSA 415-1310

July 17, 2002 MEMORANDUM TO: Richard Laufer, Chief Section I-2, Project Directorate I Division of Licensing and Project Management FROM: F. Mark Reinhart, Chief/RA/ Mark Caruso for/

Licensing Section Probabilistic Safety Assessment Branch Division of Systems Safety and Analysis

SUBJECT:

SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)

In response to your request, the Probabilistic Safety Assessment Branch (SPSB) in the Division of Systems Safety and Analysis (DSSA) has completed its review of the licensees basis for concluding that the small array valves that return service water coolant to the ultimate heat sink do not meet criterion 4 of 10CFR 50.36(2)(ii)(c)(D) for inclusion in technical specifications. Our input for the staff safety evaluation is attached.

In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, we accept the licensees conclusion that criterion 4 is not met for these valves, i.e.,

that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.

Docket Nos. 50-387, 50-388

Attachment:

Safety Evaluation DISTRIBUTION SPSB R/F MCaruso DOCUMENT NAME: G:\SPSB\caruso\susquehanna_crit4.wpd ACCESSION NO.:ML021980258 TEMPLATE NO.NRR-096 To receive a copy of this document, indicate in the box C=Copy w/o attachment/enclosure E=Copy with attachment/enclosure N = No copy OFFICE SPSB:DSSA SC:SPSB:DSSA NAME MCaruso FMReinhart/c/M. Caruso for DATE 07/17/02 07/ 17/02 OFFICIAL FILE COPY

SPSB COVER PAGE DOCUMENT: G:\SPSB\caruso\susquehanna_crit4.wpd

SUBJECT:

SAFETY EVALUATION INPUT FOR PROPOSED CHANGES TO THE SUSQUENHANNA, UNITS 1&2 TECHNICAL SPECIFICATIONS IMPLEMENTING OPERABILITY REQUIREMENTS FOR THE ULTIMATE HEAT SINK SPRAY VALVES (TAC NOS. MB2119, MB2120)

ORIGINATOR M. Caruso, 415-1310 SECRETARY: Nasreen Hasan, 415-3229 DATE: July 17, 2002

 ROUTING LIST 

NAME DATE

1. M.Caruso 07/ /02
2. M. Reinhart 07/ /02
3. 07/ /02
4. 07/ /02
5. 07/ /02
6. Secretary/Dispatcher 07/ /02 ADAMS ACCESSION #:ML0 TEMPLATE #: NRR-096

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FACILITY OPERATING LICENSE NO NPF-14, NPF-22 PP&L Susquehanna LLC SUSQUEHANNA STEAM ELECTRIC STATION DOCKET NOS. 50-387, 50-388 1 INTRODUCTION By letter dated June 1, 2001, supplemented by a letter dated June 28, 2002, PPL Susquehanna, LLC (the licensee),

requested an amendment to Facility Operating License No. NPF-14 and NPF-22 for the Susquehanna Steam Electric Station. The proposed amendment would modify Technical Specification (TS) Surveillance Requirement SR 3.7.1 to add operability requirements and surveillance requirements for the Ultimate Heat Sink (UHS) spray bypass valves and large array valves. The proposed change also reduces the allowed completion times for the conditions applicable to the Residual Heat Removal Service Water (RHRSW) system. The proposed change does not add operability requirements and surveillance requirements for the UHS small array valves. The licensees rationale for not adding requirements for the small array valves is that the small array valves do not satisfy any of the criteria in 10CFR50.36 for inclusion of limiting conditions for operation in the Technical Specifications. This evaluation addresses the licensees assessment against Criterion 4 in 10CFR50.36, i.e.,

A structure, system or component which operating experience or probabilistic risk assessment has shown to be significant to public health and safety.

Licensee assessments against other criteria in 10CFR50.36 are addressed elsewhere.

2 EVALUATION In lieu of specific guidance for addressing Criterion 4 in 10CFR 50.36, the licensee has utilized assessments of safety significance made per the Maintenance Rule (i.e., 10CFR 50.65) for the UHS components as the basis for determining whether or not the components in question are significant to public health and safety. These assessments have been made using a risk ranking process based on a probabilistic risk assessment and insights from the licensees Maintenance Rule Expert Panel and Generic Letter 89-10 (Motor Operated Valves) Expert Panel.

Using the Maintenance Rule assessment program, the licensee classified the spray bypass valves and large spray array valves as High Safety Significant. These valves provide a redundant primary means of success for the Residual Heat Removal Service Water system and Emergency Service Water system. While the small array valves can provide a back-up success path under some conditions, the time requirement for these valves to operate is greater than four hours, which allows for manual actuation of these valves if either of the primary success paths cannot be recovered. These factors are significant contributors to the relatively low risk importance of the small Attachment

array valves which has driven the licensees significance determination for these valves to a non-risk significant classification.

The staff believes that in lieu of specific staff guidance for addressing Criterion 4 in 10CFR 50.36, use of the Maintenance Rule assessment process is an acceptable means of addressing criterion 4 of 10CFR 50.36 for the small array valves at Susquehanna Units 1 and 2 because (1) it utilizes probabilistic risk assessment and also allows for insights from operating experience to be brought to bear via the expert panel review process, and (2) the licensees assessment process was found to be adequate by the NRC in the Maintenance Rule Base Line Inspection Program (Inspection Report 50-387/98-04 & 50-388/98-04, dated July 16, 1998).

3 CONCLUSION In light of the fact that the licensee has categorized the small array valves as non-risk significant as part of implementing the Maintenance Rule and the staff has found the licensees categorization process to be acceptable under the Maintenance Rule Base Line Inspection Program, the staff accepts the licensees conclusion that criterion 4 is not met for these valves, i.e., that neither operating experience or probabilistic risk assessment has shown these valves to be significant to public health and safety.

Principal contributor:

Mark Caruso Attachment

Retrieved from "https://kanterella.com/w/index.php?title=ML021980258&oldid=2701053"