ML073100423

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Request for Additional Information Regarding Technical Specification Change TS-07-04, Reactor Trip System/Engineered Safety Feature Logic, Reactor Trip Breaker Allowable Outage Time and Surveillance Testing Interval Relaxations
ML073100423
Person / Time
Site: Watts Bar Tennessee Valley Authority icon.png
Issue date: 11/20/2007
From: Moroney B
NRC/NRR/ADRO/DORL/LPLII-2
To: Campbell W
Tennessee Valley Authority
Moroney B, NRR/DORL, 415-3974
References
TAC MD5880
Download: ML073100423 (7)


Text

November 20, 2007 Mr. William R. Campbell, Jr.

Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801

SUBJECT:

WATTS BAR NUCLEAR PLANT, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING TECHNICAL SPECIFICATION CHANGE TS-07-04, REACTOR TRIP SYSTEM/ENGINEERED SAFETY FEATURE LOGIC, REACTOR TRIP BREAKER ALLOWABLE OUTAGE TIME AND SURVEILLANCE TESTING INTERVAL RELAXATIONS (TAC NO. MD5880)

Dear Mr. Campbell:

By letter dated June 8, 2007, the Tennessee Valley Authority (TVA, the licensee) submitted a proposed license amendment that affects several technical specification sections to allow relaxations of various reactor trip system/engineered safety feature logic completion times, bypass test times, and surveillance testing intervals through implementation of Technical Specification Task Force (TSTF) 418, Revision 2 and TSTF 411, Revision 1.

In order for the Nuclear Regulatory Commission staff to complete its review of the information provided by the licensee, we request that TVA provide responses to the enclosed request for additional information (RAI). Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI by December 14, 2007. If you have any questions about this material, please contact me at (301) 415-3974.

Sincerely,

/RA/

Brendan T. Moroney, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-390

Enclosure:

RAI cc w/enclosure: See next page

ML073100423 *By memo NRR-088 OFFICE LPL2-2/PM LPL2-2/LA EICB/BC APLA/BC LPL2-2/BC NAME BMoroney RSola WKemper* MRubin* TBoyce DATE 11 / 15 /07 11 / 14 /07 10/12/07 10/15/07 11/ 20 /07 William R. Campbell, Jr.

Tennessee Valley Authority WATTS BAR NUCLEAR PLANT cc:

Mr. Gordon P. Arent Ms. Beth A. Wetzel, Manager New Generation Licensing Manager Corporate Nuclear Licensing and Tennessee Valley Authority Industry Affairs 5A Lookout Place Tennessee Valley Authority 1101 Market Street 4X Blue Ridge Chattanooga, TN 37402-2801 1101 Market Street Chattanooga, TN 37402-2801 Mr. Ashok S. Bhatnagar Senior Vice President Mr. Masoud Bajestani, Vice President Nuclear Generation Development Watts Bar Unit 2 and Construction Watts Bar Nuclear Plant Tennessee Valley Authority Tennessee Valley Authority 6A Lookout Place P.O. Box 2000, EQB 1B 1101 Market Street Spring City, TN 37381 Chattanooga, TN 37402-2801 Mr. Michael K. Brandon, Manager Mr. James R. Douet Licensing and Industry Affairs Vice President Watts Bar Nuclear Plant Nuclear Support Tennessee Valley Authority Tennessee Valley Authority P.O. Box 2000 3R Lookout Place Spring City, TN 37381 1101 Market Street Chattanooga, TN 37402-2801 Mr. Michael J. Lorek, Plant Manager Watts Bar Nuclear Plant Mr. H. Rick Rogers Tennessee Valley Authority Vice President P.O. Box 2000 Nuclear Engineering & Technical Services Spring City, TN 37381 Tennessee Valley Authority 3R Lookout Place Senior Resident Inspector 1101 Market Street Watts Bar Nuclear Plant Chattanooga, TN 37402-2801 U.S. Nuclear Regulatory Commission 1260 Nuclear Plant Road Mr. Michael D. Skaggs, Site Vice President Spring City, TN 37381 Watts Bar Nuclear Plant Tennessee Valley Authority County Executive P.O. Box 2000 375 Church Street Spring City, TN 37381 Suite 215 Dayton, TN 37321 General Counsel Tennessee Valley Authority County Mayor 6A West Tower P. O. Box 156 400 West Summit Hill Drive Decatur, TN 37322 Knoxville, TN 37902 Mr. Lawrence E. Nanney, Director Mr. John C. Fornicola, Manager Division of Radiological Health Nuclear Assurance Dept. of Environment & Conservation Tennessee Valley Authority Third Floor, L and C Annex 3R Lookout Place 401 Church Street 1101 Market Street Nashville, TN 37243-1532 Chattanooga, TN 37402-2801 Mr. Larry E. Nicholson, General Manager Performance Improvement Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801

REQUEST FOR ADDITIONAL INFORMATION WATTS BAR NUCLEAR PLANT, UNIT 1 TECHNICAL SPECIFICATIONS CHANGE REQUEST TS-07-04 DOCKET 05-390 To support Nuclear Regulatory Commission assessment of the acceptability of the proposed changes, please provide the response to the following items:

1. The proposed change to Condition P of TS Section 3.3.1, page 3.3-6 cites Technical Specification Task Force (TSTF) 411, Rev. 1, as the basis for the change. This is apparently an error since the revised times do not match those in TSTF-411. Also, it is not consistent with item 7 on page E1-2 and the revised technical specification (TS) bases, page B 3.3-47, which refer to TSTF-418, Rev. 2. Please check the referenced TSTF and update the submittal as appropriate.
2. Condition K of TS Section 3.3.2, page 3.3-28 applies to RWST Level - Low coincident with Safety Injection and coincident with Containment Sump Level - High. This is also noted as condition K in TSTF-418, Rev. 2; page 3.3.2 -5. The revised completion times of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for required action K.1, 78 hours9.027778e-4 days <br />0.0217 hours <br />1.289683e-4 weeks <br />2.9679e-5 months <br /> for required action K.2.1, and 108 hours0.00125 days <br />0.03 hours <br />1.785714e-4 weeks <br />4.1094e-5 months <br /> for K.2.2 are not consistent with the revised completion times of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for K.1, 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for K.2.1, and 42 hours4.861111e-4 days <br />0.0117 hours <br />6.944444e-5 weeks <br />1.5981e-5 months <br /> for K.2.2 noted on page 3.3.2 -5 of TSTF-418, Rev. 2. The word additional has also been deleted in the submittal but it remains in the text of the required action in the TSTF. Please explain the justification for the differences and provide appropriate reference for this change. If plant specific evaluations have been made for these changes, then please provide us with the reference documents. Also please update the bases section for this item as appropriate.
3. The analysis for Westinghouse Commercial Atomic Power (WCAP) topical reports WCAP-14333 and WCAP-15376 assumed that maintenance on master and slave relays, logic cabinets, and analog channels while at power occurs only after a component failure, and that preventive maintenance does not occur. The topical reports do not preclude the practice of at-power preventive maintenance but limits the total time a component is unavailable due to corrective or preventive maintenance to the values used in the analysis.

Confirm that the unavailability for components evaluated in WCAP-14333 and WCAP-15376 are consistent with the plant specific estimates at Watts Bar Nuclear Plant (WBN), Unit 1 and do not exceed those assumed in the analysis.

4. Describe the program to be implemented to monitor reactor trip system (RTS) and engineered safety features actuation system (ESFAS) structures systems and components (SSCs) to ensure equipment unavailability and component failure data remains consistent with WCAP-15376 and WCAP-14333 modeling assumptions. Refer to Regulatory Guide (RG) 1.174 Section 2.3, ADefine Implementation and Monitoring Program.@
5. Provide an assessment of external events risk impact, including seismic, fire and external floods/high wind, with respect to the proposed completion times (CT) and surveillance test intervals extensions, per RG 1.174 Section 2.2.4, AAcceptance Guidelines,@ and RG 1.177 Section 2.3.2, AScope of the PRA [Probability Risk Assessment] for TS Applications.@

Include any seismic vulnerabilities associated with instrumentation/logic systems or components. Discuss the risk impact of WCAP-14333 and WCAP-15376 on fire screening criteria and quantification of fire sequences previously screened from the analysis. In addition, confirm that the combined total core damage frequency (CDF) from external and internal events will remain less than the RG 1.174 base CDF of 1E-4 per year.

6. Provide a discussion on the following aspects of PRA quality for WBN, Unit 1.

(a) Provide the date of WBN, Unit 1 PRA industry peer review and date of certification.

Provide details of any licensee self assessments performed against RG 1.200, AAn Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk -Informed Activities.@

(b) Reference PRA quality assurance programs/procedures, including expected PRA revision schedules.

(c) Address PRA adequacy and completeness with respect to evaluating the proposed CT and bypass test times under Tier 3 configuration risk management.

Describe the Tier 3 evaluation, including modified procedures/risk assessment methodology, as appropriate, for SSCs incorporating the proposed WCAP-14333 and WCAP-15376 CT and bypass test times. Discuss the representative RTS and ESFAS actuation signals in the WBN, Unit 1 plant risk matrix sufficient to perform Tier 3 evaluations on these SSCs to ensure that Tier 3 evaluations reflect the implementation of WCAP-15376 and WCAP-14333.

(d) Address plant-specific design or operational modifications not reflected in the WCAP-14333/WCAP15376 evaluation for WBN, Unit 1, but implemented prior to this application that are related to or could impact this application. Justify the acceptability of not including these modifications in the PRA as part of this application.

7. Enclosure 1, Page E1-14, references equipment restrictions that will be put in place (WCAP-15376 Tier 2). The referenced restrictions appear to be inconsistent with the restrictions stated for WCAP-15376, Section 8.5. Specifically, clarify the applicability of a logic cabinet out-of-service with the associated reactor trip breaker out-of-service (i.e., 3rd bullet).
8. Confirm that the restrictions identified in the license amendment request (Enclosure 1, Pages 13 and 14) for the implementation of WCAP-15376 and WCAP-14333 are intended to be regulatory commitments.