ML100620799
| ML100620799 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 03/10/2010 |
| From: | Michael Mahoney Plant Licensing Branch III |
| To: | Allen B FirstEnergy Nuclear Operating Co |
| Mahoney, M NRR/DORL/LPLIII- 2 415-3867 | |
| References | |
| tac me3427 | |
| Download: ML100620799 (4) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 March 10, 2010 Mr. Barry S. Allen Site Vice President FirstEnergy Nuclear Operating Company Davis-Besse Nuclear Power Station Mail Stop A-DB-3080 5501 North State Route 2 Oak Harbor, OH 43449-9760
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - UPCOMING STEAM GENERATOR TUBE INSERVICE INSPECTION (TAC NO. ME3427)
Dear Mr. Allen:
Inservice inspections of steam generator (SG) tubes playa vital role in assuring SG tube integrity. A telephone conference will be arranged with members of your staff to discuss the ongoing results of the SG tube inspections to be conducted during the upcoming Davis-Besse Nuclear Power Station, Unit 1, refueling outage. This call will occur after the majority of the tubes have been inspected, but before the SG inspection activities have been completed (when approximately 70 percent of the inspection results have been analyzed). Enclosed is a list of discussion points to facilitate this call.
The U.S. Nuclear Regulatory Commission (NRC) staff will document a summary of the conference call, including any material that you provide to the NRC staff in support of the call.
Should you have any questions, you can contact me at 301-415-3867.
N Michael Mahoney, roject Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-346
Enclosure:
Steam Generator Tube Inspection Discussion Points cc w/encl: Distribution via Listserv
STEAM GENERATOR TUBE INSPECTION DISCUSSION POINTS The following discussion paints have been prepared to facilitate the conference call arranged with the licensee to discuss the results of the steam generator (SG) tube inspections to be conducted during the upcoming Davis-Besse Nuclear Power Station spring 2010 outage. This conference call is scheduled to occur towards the end of the planned SG tube inspections, but before the unit completes the inspections and repairs.
The U.S. Nuclear Regulatory Commission staff plans to document a summary of the conference call as well as any material that is provided in support of the call.
- 1.
Discuss any trends in the amount of primary-to-secondary leakage observed during the recently completed cycle.
- 2.
Discuss whether any secondary side pressure tests were performed during the outage and the associated results.
- 3.
Discuss any exceptions taken to the industry guidelines.
- 4.
For each SG, provide a description of the inspections performed including the areas examined and the probes used (e.g., dents/dings. sleeves, expansion-transition). the scope of the inspection (e.g.. 100 percent of dents/dings greater than 5 volts and a 20 percent sample between 2 and 5 volts), and the expansion criteria.
- 5.
For each area examined (e.g.. tube supports. dent/dings, sleeves, etc), provide a summary of the number of indications identified to-date for each degradation mode (e.g.. number of circumferential primary water stress-corrosion cracking indications at the expansion transition). For the most significant indications in each area. provide an estimate of the severity of the indication (e.g.* provide the voltage, depth. and length of the indication). In particular, address whether tube integrity (structural and accident induced leakage integrity) was maintained during the previous operating cycle. In addition, discuss whether any location exhibited a degradation mode that had not previously been observed at this location at this unit (e.g., observed circumferential primary water stress-corrosion cracking at the expansion transition for the first time at this unit).
- 6.
Describe repair/plugging plans.
- 7.
Describe in-situ pressure test and tube pull plans and results (as applicable and if available).
- 8.
Discuss the following regarding loose parts:
what inspections are performed to detect loose parts a description of any loose parts detected and their location within the SG (including the source or nature of the loose part. if known)
- 2 if the loose parts were removed from the SG indications of tube damage associated with the loose parts
- 9.
Discuss the scope and results of any secondary side inspection and maintenance activities (e.g., in-b undle visual inspections, feedring inspections, sludge lancing, assessing deposit loading, etc).
- 10. Discuss any unexpected or unusual results.
- 11. Provide the schedule for SG-related activities during the remainder of the current outage.
March 10,2010 Mr. Barry S. Allen Site Vice President FirstEnergy Nuclear Operating Company Davis-Besse Nuclear Power Station Mail Stop A-DB-3080 5501 North State Route 2 Oak Harbor, OH 43449-9760
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - UPCOMING STEAM GENERATOR TUBE INSERVICE INSPECTION (TAC NO. ME3427)
Dear Mr. Allen:
Inservice inspections of steam generator (SG) tubes playa vital role in assuring SG tube integrity. A telephone conference will be arranged with members of your staff to discuss the ongoing results of the SG tube inspections to be conducted during the upcoming Davis-Besse Nuclear Power Station, Unit 1, refueling outage. This call will occur after the majority of the tubes have been inspected, but before the SG inspection activities have been completed (when approximately 70 percent of the inspection results have been analyzed). Enclosed is a list of discussion points to facilitate this call.
The U.S. Nuclear Regulatory Commission (NRC) staff will document a summary of the conference call, including any material that you provide to the NRC staff in support of the call.
Should you have any questions, you can contact me at 301-415-3867.
Sincerely, IRA!
Michael Mahoney, Project Manager Plant Licensing Branch 111-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-346
Enclosure:
Steam Generator Tube Inspection Discussion Points cc w/encl: Distribution via Listserv DISTRIBUTION:
PUBLIC RidsNrrPMMMahoney LPL3-2 RlF RidsNrrLATHarris Resource RidsNrrDorlLpl3-2 Resource RidsRgn3MailCenter Resource ADAMS Accession No ML100620799 NRR-106
{)FFICE LPL3-2/PM LPL3-2/LA LPL3-2/BC NAME MMahoney THarris SCampbell DATE 03/06/10 03/05/10 03/10/10