ML072140023
| ML072140023 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 08/08/2007 |
| From: | Robert Kuntz NRC/NRR/ADRO/DORL/LPLIII-2 |
| To: | Crane C Exelon Generation Co |
| Kuntz, Robert , NRR/DLPM, 415-3733 | |
| References | |
| TAC MD3855, TAC MD3856 | |
| Download: ML072140023 (6) | |
Text
August 8, 2007 Mr. Christopher M. Crane President and Chief Nuclear Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
BYRON STATION, UNIT NOS. 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION RELATED TO RELIEF REQUEST I3R-02 (TAC NOS. MD3855 AND MD3856)
Dear Mr. Crane:
By letter to the Nuclear Regulatory Commission (NRC) dated February 14, 2006, Exelon Generation Company, LLC submitted Relief Request I3R-02, related to the use of risk-informed inservice inspection requirements, for the Byron Station, Unit Nos. 1 and 2.
The NRC staff is reviewing your submittal and has determined that additional information is required to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on August 1, 2007, it was agreed that you would provide a response within 30 days from the date of this letter.
The NRC staff considers that timely responses to requests for additional information help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-3733.
Sincerely,
/RA/
Robert F. Kuntz, Project Manager Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. STN 50-454 and STN 50-455
Enclosure:
Request for Additional Information cc w/encl: See next page
Mr. Christopher M. Crane August 8, 2007 President and Chief Nuclear Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
BYRON STATION, UNIT NOS. 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION RELATED TO RELIEF REQUEST I3R-02 (TAC NOS. MD3855 AND MD3856)
Dear Mr. Crane:
By letter to the Nuclear Regulatory Commission (NRC) dated February 14, 2006, Exelon Generation Company, LLC submitted Relief Request I3R-02, related to the use of risk-informed inservice inspection requirements, for the Byron Station, Unit Nos. 1 and 2.
The NRC staff is reviewing your submittal and has determined that additional information is required to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on August 1, 2007, it was agreed that you would provide a response within 30 days from the date of this letter.
The NRC staff considers that timely responses to requests for additional information help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-3733.
Sincerely,
/RA/
Robert F. Kuntz, Project Manager Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. STN 50-454 and STN 50-455
Enclosure:
Request for Additional Information cc w/encl: See next page DISTRIBUTION:
PUBLIC LPL3-2 R/F RidsNrrDorlLpl3-2 RidsNrrPMRKuntz RidsNrrLAEWhitt RidsAcrsAcnwMailCenter RidsOgcRp RidsRgn3MailCenter RidsNrrDorlDpr ADAMS Accession Number: ML072140023 OFFICE LPL3-2/PM LPL3-2/LA LPL3-2/BC NAME RKuntz EWhitt RGibbs (TWengert for)
DATE 8/7/07 8/7/07 8/8/07 OFFICIAL RECORD COPY
Byron Station, Unit Nos. 1 and 2 cc:
Illinois Emergency Management Agency Division of Disaster Assistance &
Preparedness 1035 Outer Park Dr Springfield, IL 62704 Document Control Desk - Licensing via e-mail Mr. Dwain W. Alexander, Project Manager via e-mail Howard A. Learner Environmental Law and Policy Center of the Midwest 35 East Wacker Drive Suite 1300 Chicago, IL 60601-2110 U.S. Nuclear Regulatory Commission Byron Resident Inspectors Office via e-mail Ms. Lorraine Creek RR 1, Box 182 Manteno, IL 60950 Chairman, Ogle County Board P.O. Box 357 Oregon, IL 61061 Mrs. Phillip B. Johnson 1907 Stratford Lane Rockford, IL 61107 Attorney General 500 S. Second Street Springfield, IL 62701 Plant Manager - Byron Station via e-mail Site Vice President - Byron Station via e-mail Senior Vice President - Operations Support via e-mail Chairman Will County Board of Supervisors Will County Board Courthouse Joliet, IL 60434 Director - Licensing and Regulatory Affairs via e-mail Manager Regulatory Assurance - Byron via e-mail Associate General Counsel via e-mail Vice President - Regulatory Affairs via e-mail Manager Licensing - Braidwood/Byron via e-mail Senior Vice President - Midwest Operations via e-mail Vice President - Regulatory Affairs via e-mail Manager Licensing - Braidwood, Byron and LaSalle via e-mail Senior Vice President - Midwest Operations via e-mail Mr. Barry Quigley 3512 Louisiana Rockford, IL 61108
Enclosure REQUEST FOR ADDITIONAL INFORMATION BYRON STATION, UNITS 1 AND 2 DOCKET NOS. STN 50-454 AND STN 50-455 In reviewing the Exelon Generation Companys (Exelons) submittal dated February 14, 2006, related to Relief Request I3R-02, which requested the use of risk-informed inservice inspection requirements, for the Byron Station, Units 1 and 2 (Byron), the NRC staff has determined that the following information is needed in order to complete its review:
Background
Relief Request I3R-02 states that in lieu of the evaluation and sample expansion requirements in EPRI TR-112657, Section 3.6.6.2, Byron will utilize the requirements of Subarticle - 2430, Additional Examinations contained in Code Case N-578-1. The alternative criteria for additional examinations contained in Code Case N-578-1 provides a more refined methodology for implementing necessary additional examinations. Relief Request I3R-02 also states that to supplement the requirements of EPRI TR-112657, Table 4-1, Summary of Degradation-Specific Inspection Requirements and Examination Methods, Byron will utilize the provisions listed in Table 1, Examination Category R-A, Risk-Informed Piping Examinations contained in Code Case N-578-1.
The NRC staff notes that Regulatory Guide (RG) 1.193 ASME Code Cases Not Approved for Use, dated August 2005, lists the code cases that the NRC has determined to not be acceptable for use on a generic basis. Code Case N-578-1 is listed in Table 2 Unacceptable Section XI Code Cases of RG 1.193. The summary given in Table 2 of RG 1.193 states in regards to Code Case N-578-1 that:
(1) The Code Case does not address inspection strategy for existing augmented and other inspection programs such as intergranular stress corrosion cracking (IGSCC), flow-assisted corrosion (FAC), microbiological corrosion (MIC), and pitting.
(2) The Code Case does not provide system-level guidelines for change in risk evaluation to ensure that the risk from individual system failures will be kept small and dominant risk contributors will not be created.
Requests for Additional Information 1.
It is not clear what is meant by a more refined methodology for implementing additional examinations. How do the alternative criteria for additional examinations contained in Code Case N-578-1 provide a more refined methodology?
2.
Please verify that any additional examinations required due to the identification of flaws or relevant conditions will be conducted during the current outage.
3.
Discuss how ultrasonic examinations will be performed for each degradation mechanism. What volumes will be examined and what techniques will be used?
4.
Please describe how volumetric examinations will be performed. Will volumetric examinations include the volume required for ASME Section XI examinations? Will ASME Section XI, Appendix VIII qualified examiners and procedures be used for all volumetric exams? Will the examination volume be scanned for both axial and transverse indications for all exams?
5.
How will dissimilar metal welds be addressed? Discuss in detail the technical basis for including alloy 600 pressure-retaining dissimilar metal welds in your risk-informed inservice inspection, rather than a separate augmented program to the RI-ISI program.
6.
Provide information regarding: examinations/system/components/degradation mechanisms/class, etc. similar to that provided in Attachment 1 of the Callaway submittal dated March 28, 2006 (Agencywide Documents Access and Management System Accession No. ML061010704). The information should show a summary of the changes in inspections from the Section XI program and changes from the previous risk informed-inservice inspection (RI-ISI) program to the proposed RI-ISI program.