ML101650770
| ML101650770 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force |
| Issue date: | 06/17/2010 |
| From: | Rosenberg S Division of Policy and Rulemaking |
| To: | Technical Specifications Task Force |
| References | |
| TAC ME2950 TSTF-517, Rev 0 | |
| Download: ML101650770 (5) | |
Text
June 17, 2010 Technical Specifications Task Force (TSTF) 11921 Rockville Pike, Suite 100 Rockville, MD 20852
SUBJECT:
WITHDRAWAL OF TSTF-517, REVISION 0, ALLOWANCE FOR NON-TS COOLING/VENTILATION SYSTEMS DEGRADATION ON SUPPORT SYSTEM OPERABILITY (TAC NO. ME2950)
Dear Members of the TSTF:
By letter dated October 28, 2009 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML093020066), the Technical Specifications Task Force (TSTF) submitted for U.S. Nuclear Regulatory Commission (NRC) staff review Traveler TSTF-517, Revision 0, Allowance for Non-TS Cooling/Ventilation Systems Degradation on Support System Operability. The scope of the Traveler was limited to cooling or ventilation systems not separately addressed by Technical Specifications (TS).
During the acceptance review, the NRC staff identified concerns with TSTF-517, Revision 0, and discussed them with the TSTF in a telephone conference held on April 29, 2010. Specifically, the staff noted that TSTF-517 proposed to use a simplified risk assessment methodology that was similar to the methodology used by approved Traveler TSTF-427-A, Revision 2. The staff noted that TSTF-427-A addressed the unavailability of passive hazard barriers not separately addressed by TS and that a simplified risk assessment was justified because the impact of unavailability of these barriers only affected a low probability initiating event (high energy line break). The impact of cooling and ventilation system unavailability, however, is more significant because it renders supported components unavailable for any initiating event and has the same impact as a supported component being inoperable for other causes. Additionally, plant-specific risk models should be capable of a direct assessment of risk due to the unavailability of cooling or ventilation support systems, which is not the case for passive hazard barriers. Finally, the staff indicated that the guidance in NEI 06-09, Revision 0, approved by the staff to support Risk Informed Initiative 4b, is the appropriate method to determine a risk-informed completion time for cooling or ventilation support system unavailability.
By letter dated May 13, 2010, the TSTF withdrew Traveler TSTF-517 from further NRC review.
In the withdrawal letter, you indicated that the methodology used to support TSTF-517 is not sufficiently rigorous to support the proposed changes and that the methodology employed for Risk Informed Initiative 4b is better suited to this application. You further indicated that this is being pursued in a separate Traveler.
Based upon your withdrawal of TSTF-517, Revision 0, the NRC staff will terminate review and TAC No. ME2950 will be closed.
TSTF If you have any questions regarding this matter, please contact Barry Miller at (301) 415-4117.
Sincerely,
/RA/
Stacey L. Rosenberg, Chief Licensing Processes Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No: 753 cc: See next page
TSTF If you have any questions regarding this matter, please contact Barry Miller at (301) 415-4117.
Sincerely,
/RA/
Stacey L. Rosenberg, Chief Licensing Processes Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No: 753 cc: See next page DISTRIBUTION:
PUBLIC RidsOgcMailCenter RidsNrrDssScvb RidsNrrDraApla RidsNrrDirsItsb PLPB Reading File RidsNrrDpr RidsNrrDprPlpb Barry Miller Carl Schulten AHowe ADAMS ACCESSION NO.: ML101650770 OFFICE PLPB/PM PLPB/LA SCVB/BC APLA/BC ITSB/BC PLPB/BC NAME BMiller EHylton RDennig DHarrison RElliott SRosenberg DATE 06/ 15 /10 06/ 15 /10 06/ 15 /10 06/ 15 /10 06/ 15 /10 6/17/10 OFFICIAL RECORD COPY
Technical Specifications Task Force Mailing List cc:
Technical Specifications Task Force Reene' V. Gambrell 11921 Rockville Pike Duke Energy Suite 100 Mailcode: ON03RC Attention: Donald Hoffman 7800 Rochester Highway Rockville, MD 20852 Seneca, SC 29672 Telephone: 301-984-4400 Telephone: 864-885-3364 E-mail: donaldh@excelservices.com E-mail: RVGambrell@duke-energy.com Kenneth Schrader Brian Mann Diablo Canyon Power Plant EXCEL Services Corporation Building 104/5/21A 11921 Rockville Pike, Suite 100 P.O. Box 56 Rockville, MD 20852 Avila Beach, CA 93424 Telephone: 301-984-4400 Telephone: 805-545-4328 E-mail: brianm@excelservices.com E-mail: kjse@pge.com Donald W. Gregoire Energy Northwest Columbia Generating Station Mail Drop PE20 PO Box 968 Richland, WA 99352-0968 Telephone: 509-377-8616 E-mail: dwgregoire@energy-northwest.com Thomas Raidy Southern California Edison Mail Stop D-3-E P.O. Box 128 San Clemente, CA 92672 Telephone: 949-368-7582 E-mail: Tom.Raidy@sce.com Wendy E. Croft Exelon Nuclear 200 Exelon Way, Suite 340 Kennett Square, PA 19348 Telephone: 610-765-5726 E-mail: Wendi.Croft@exeloncorp.com