ML082940187
| ML082940187 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 10/28/2008 |
| From: | John Lamb Watts Bar Special Projects Branch |
| To: | Campbell W Tennessee Valley Authority |
| Lamb John G./NRR/DORL, 415-3100 | |
| References | |
| TAC MD9596 | |
| Download: ML082940187 (5) | |
Text
October 28, 2008 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 THE RELIEF REQUEST FOR THE RISK-INFORMED INSERVICE INSPECTION PROGRAM (TAC NO. MD9596)
Dear Mr. Campbell:
By letter dated December 4, 2007 (Agencywide Documents Access and Management System Accession No. ML073390086), Tennessee Valley Authority (TVA) proposed a relief request (RR) for the Watts Bar Nuclear Plant (WBN), Unit 1, Risk-Informed (RI) Inservice Inspection (ISI)
Program. The proposed RR would modify the methodology for the the RI-ISI program and would be used for the second ISI interval, which began May 27, 2007. TVA proposes to use the alternative methodology described in Electric Power Research Institute Technical Report TR-112657, Revision B-A, Revised Risk-Informed Inservice Inspection Evaluation Procedure, and the associated U.S. Nuclear Regulatory Commission (NRC) staff safety evaluation.
The staff has reviewed the information provided by TVA and has determined that additional information is required to complete its evaluation of the proposed relief request. The specific questions are detailed in the enclosed request for additional information (RAI). Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI within 30 days of the date of this letter.
If you have any questions regarding this issue, please feel free to contact me at (301) 415-3100.
Sincerely,
/RA/
John G. Lamb, Senior Project Manager Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-390
Enclosure:
RAI cc w/enclosure: See next page
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 THE RELIEF REQUEST FOR THE RISK-INFORMED INSERVICE INSPECTION PROGRAM (TAC NO. MD9596)
Dear Mr. Campbell:
By letter dated December 4, 2007 (Agencywide Documents Access and Management System Accession No. ML073390086), Tennessee Valley Authority (TVA) proposed a relief request (RR) for the Watts Bar Nuclear Plant (WBN), Unit 1, Risk-Informed (RI) Inservice Inspection (ISI)
Program. The proposed RR would modify the methodology for the the RI-ISI program and would be used for the second ISI interval, which began May 27, 2007. TVA proposes to use the alternative methodology described in Electric Power Research Institute Technical Report TR-112657, Revision B-A, Revised Risk-Informed Inservice Inspection Evaluation Procedure, and the associated U.S. Nuclear Regulatory Commission (NRC) staff safety evaluation.
The staff has reviewed the information provided by TVA and has determined that additional information is required to complete its evaluation of the proposed relief request. The specific questions are detailed in the enclosed request for additional information (RAI). Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI within 30 days of the date of this letter.
If you have any questions regarding this issue, please feel free to contact me at (301) 415-3100.
Sincerely,
/RA/
John G. Lamb, Senior Project Manager Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-390
Enclosure:
RAI cc w/enclosures: See next page DISTRIBUTION:
PUBLIC RidsNrrPMJLamb S. Dinsmore, NRR RidsNrrDraApla LP-WB R/F RidsNrrLABClayton RidsOgcRp RidRgn2MailCenter RidsNrrDorlLpwb RidsAcrsAcnwMailCenter RidsNrrPMPMilano ADAMS Accession Number: ML082940187 OFFICE LP-WBB/PM LP-WB/LA APLA/BC LP-WB/BC NAME JLamb BClayton MRubin LRaghavan DATE 10/ 21 /08 10/ 21 /08 10/ 27 /08 10/ 28 /08 OFFICIAL RECORD COPY
William R. Campbell, Jr.
Tennessee Valley Authority WATTS BAR NUCLEAR PLANT cc:
Mr. Gordon P. Arent New Generation Licensing Manager Tennessee Valley Authority 5A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Ashok S. Bhatnagar Senior Vice President Nuclear Generation Development and Construction Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Vice President Nuclear Support Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Michael J. Lorek Vice President Nuclear Engineering & Technical Services Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 General Counsel Tennessee Valley Authority 6A West Tower 400 West Summit Hill Drive Knoxville, TN 37902 Mr. John C. Fornicola, Manager Nuclear Assurance Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Larry E. Nicholson, General Manager Performance Improvement Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Michael D. Skaggs Site Vice President Watts Bar Nuclear Plant Tennessee Valley Authority P. O. Box 2000 Spring City, TN 37381 Mr. Michael A. Purcell Senior Licensing Manager Nuclear Power Group Tennessee Valley Authority 4K Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Ms. Beth A. Wetzel, Manager Corporate Nuclear Licensing and Industry Affairs Tennessee Valley Authority 4K Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Masoud Bajestani, Vice President Watts Bar Unit 2 Watts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381 Mr. Michael K. Brandon, Manager Licensing and Industry Affairs Watts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381 Mr. Gregory A. Boerschig, Plant Manager Watts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381 Senior Resident Inspector Watts Bar Nuclear Plant U.S. Nuclear Regulatory Commission 1260 Nuclear Plant Road Spring City, TN 37381 County Executive 375 Church Street Suite 215 Dayton, TN 37321 County Mayor P. O. Box 156 Decatur, TN 37322 Mr. Lawrence E. Nanney, Director Division of Radiological Health Dept. of Environment & Conservation Third Floor, L and C Annex 401 Church Street Nashville, TN 37243-1532
Enclosure REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST FOR RISK-INFORMED INSERVICE INSPECTION PROGRAM WATTS BAR NUCLEAR PLANT, UNIT 1 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-390 By letter dated December 4, 2007 (Agencywide Documents Access and Management System Accession No. ML073390086), Tennessee Valley Authority (TVA) proposed a relief request (RR) for the Watts Bar Nuclear Plant (WBN), Unit 1, Risk-Informed (RI) Inservice Inspection (ISI)
Program. The proposed RR would modify the methodology for the the RI-ISI program and would be used for the second ISI interval, which began May 27, 2007. TVA proposes to use the alternative methodology described in Electric Power Research Institute Technical Report TR-112657, Revision B-A, Revised Risk-Informed Inservice Inspection Evaluation Procedure, and the associated U.S. Nuclear Regulatory Commission staff safety evaluation.
The staff has reviewed the information provided by TVA and has determined that additional information is required to complete its evaluation of the proposed RR. The specific questions are detailed below.
Question 1 Section 3.1 of the submittal states that, segments were defined as continuous runs of piping whose failure would result in the same consequence. Section 3.4 further defines risk groups as welds susceptible to the same degradation mechanism and whose failure would result in the same consequence. Table 3.1 identifies segments and Table 3.4 identifies risk groups, and the entries in the two tables are not easily comparable.
Please clarify what the same consequence in Section 3.1 means (e.g., is it the consequential failure of exactly the same functions and equipment, or simply the same consequence category?) Based on this clarification, please explain how the number of segments in a system in Table 3.1 is related to the number of risk groups in the same system in Table 3.4.
Question 2 Section 3.5.1, Additional Examinations (page E1-9 of the submittal), presents the criteria for engineering evaluation and additional examinations. The submittal states that "Additional examinations will be performed on those elements with the same root cause conditions or degradation mechanisms. The additional examinations will include high-risk significant elements and medium risk significant elements, if needed, up to a number equivalent to the number of elements required to be inspected on the segment or segments during the current outage. If unacceptable flaws or relevant conditions are again found similar to the initial problem, the remaining elements identified as susceptible will be examined." Please clarify when these remaining elements will be examined.
Question 3 Table 3.5 shows that, in Category 4, there are 21 elements selected for inspection in the Reactor Coolant system (RCS) system. However, Table 3.6 shows only 20 Category 4 inspection locations in the RCS system. Please clarify this apparent inconsistency.