TSTF-05-13, Technical Specification Task Force (TSTF) Response to May 25, 2005 Notice of Opportunity to Comment on Model Safety Evaluation on Technical Specification Improvement Re Revision to the Completion Time in STS 3.6.1.3, Primary Containment I
| ML052090188 | |
| Person / Time | |
|---|---|
| Issue date: | 07/25/2005 |
| From: | Crowthers M, Infanger P, Sparkman W, Woods B B & W Owners Group, BWR Owners Group, Combustion Engineering Owners Group, Technical Specifications Task Force, Westinghouse Owners Group |
| To: | NRC/ADM/DAS/RDB |
| References | |
| TSTF-05-13 | |
| Download: ML052090188 (4) | |
Text
TECHNICAL SPECII;CATIONS TASK FIORCE TSTF A JiOIJV 0 W7VERS GR O 'PA C7 VIT'Y July 25, 2005 TSTF-05-13
Dear Sir or Madam:
Chief, Rules and Directives Branch Division of Administrative Services Office of Administration Mail Stop: T-6 D59 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Technical Specification Task Force (TSTF) Response to the May 25, 2005 Notice of Opportunity to Comment on Model Safety Evaluation on Technical Specification Improvement Regarding Revision to the Completion Time in STS 3.6.1.3, "Primary Containment Isolation Valves," for General Electric Boiling Water Reactors Using the Consolidated Line Item Improvement Process Enclosed for NRC consideration are comments on the subject May 25, 2005 Federal Register Notice.
The Technical Specification Task Force (TSTF) is an activity sponsored by the Westinghouse Owners Group, the Boiling Water Reactors Owners Group, and the Babcock and Wilcox Owners Group. The TSTF is the author of the generic change to the Improved Standard Technical Specifications (known as a Traveler), TSTF-454, Revision 0, "Increase PCIV Completion Times from 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days (NEDC-33046)," that is the subject of the Federal Register Notice.
Should you have any questions, please do not hesitate to contact us.
Wesley Spa nan (WOG) Michael Crowthers (BWROG)
_ __ P 4 Brian Woods (WOG/CE) Paul Infang BWOG)
Enclosure cc: Thomas H. Boyce, Technical Specifications Section, NRC C ool Bhalchandra Vaidya, NRC 11921 Rockville Pike, Suite 100, Rockville, MD 20852 BWR Phone: 301-984-4400, Fax: 301-984-7600 OWNERS' GROUP Email: tstf@excelservices.com Owners GroupI Administered by EXCEL Services Corporation
Technical Specification Task Force (TSTF) Response to the May 25, 2005 Notice of Opportunity to Comment on Model Safety Evaluation on Technical Specification Improvement Regarding Revision to the Completion Time in STS 3.6.1.3, "Primary Containment Isolation Valves," for General Electric Boiling Water Reactors Using the Consolidated Line Item Improvement Process (CLIIP)
We suggest that additional clarification be included in the model Safety Evaluation, as described below.
Comment I Condition 3, Condition 6, and the one required commitment of Section 3.2, Evaluation of Proposed Changes, of the model Safety Evaluation are not clear or consistent on the expectations for a containment performance assessment (i.e., large early release fraction, or LERF) as part of the configuration risk management program (CRMP). These conditions should be clarified either in the Safety Evaluation or in the CLIIP model application.
Condition 3 requires licensees to conform to the Maintenance Rule requirements of 10 CFR 50.65(a)(4) as it relates to Primary Containment Isolation Valve (PCIV)
Completion Times and the guidance of NUMARC 93.01, "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," Section 11 including a LERF and incremental conditional large early release probability (ICLERP) assessment as part of the process. In addition, Condition 6 requires the CRMP to confirm that simultaneous extended Completion Time entries in separate penetration flow paths will not exceed the Regulatory Guide 1.174 and Regulatory Guide 1.177 acceptance guidelines. The commitment required by the Safety Evaluation also requires the licensee's CRMP be enhanced to include a LERF methodology/assessment.
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Technical Specification Task Force (TSTF) Response to the May 25, 2005 Notice of Opportunity to Comment on Model Safety Evaluation on Technical Specification Improvement Regarding Revision to the Completion Time in STS 3.6.1.3, "Primary Containment Isolation Valves," for General Electric Boiling Water Reactors Using the Consolidated Line Item Improvement Process (CLIIP)
Many licensees do not currently have a probabilistic risk assessment (PRA) Level 2 model built into the CRMP for calculating a LERF risk value. Adding the LERF model will significantly delay adoption of the proposed Traveler. The containment risk management assessment is routinely addressed through qualitative methods and administrative controls. Section 11 of NUMARC 93-01 allows for qualitative assessment methods. Section 11.3.4, Assessment Methods for Power Operating Conditions, states, "Simultaneous removal from service of multiple SSCs [Structures, Systems, and Components] requires that an assessment be performed using quantitative, qualitative, or blended (quantitative and qualitative) methods. Sections 11.3.4.1 and 11.3.4.2 provide guidance regarding quantitative and qualitative considerations, respectively."
Is it the intent of the conditions and commitment to require a PRA calculation to quantify LERF risk values for the specific plant configurations each time a PCIV is inoperable?
Would this apply only when the extended Completion Time is used or only when multiple penetration flow paths are affected as discussed in Condition 6? Would it be acceptable to assess and manage the containment performance impacts by qualitative methods and administrative controls as currently allowed by NUMARC 93-01 as endorsed by Regulatory Guide 1.182? For example, an assessment program could manage containment performance risk by limiting the number of affected penetration flow paths depending on factors such as the flow path size and not require a LERF calculation for each occurrence.
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Technical Specification Task Force (TSTF) Response to the May 25, 2005 Notice of Opportunity to Comment on Model Safety Evaluation on Technical Specification Improvement Regarding Revision to the Completion Time in STS 3.6.1.3, "Primary Containment Isolation Valves," for General Electric Boiling Water Reactors Using the Consolidated Line Item Improvement Process (CLIIP)
Comment 2 Condition 6 of Section 3.2, Evaluation of Proposed Changes, requires the licensee application to provide supporting information that verifies that the potential for any cumulative risk impact of failed PCIVs and multiple PCIV extended Completion Time entries has been evaluated and is acceptable. The verb tense "has been evaluated" is confusing. Is the intent to require an assessment of the plant's design and historical experience to verify that the potential for multiple extended Completion Time entries is low? Please clarify either in the Safety Evaluation or in the CLIIP model application what the evaluation involves.
Comment 3 Condition I of Section 3.2, Evaluation of Proposed Changes, uses the terms "incremental conditional core damage frequency (ICCDP)" and "incremental conditional large early release frequency (ICLERP)". The word "frequency" in these two terms should be changed to "probability".
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