ML050870298

Rick A. Muench, Ltr Wolf Creek Generating Station, RAI, Steam Generator Tube Inspection Summary Report for Fall 2003 Outage

ML050870298
Person / Time
Site:	Callaway
Issue date:	03/30/2005
From:	Donohew J NRC/NRR/DLPM/LPD4
To:	Muench R Wolf Creek
Donohew J N, NRR/DLPM,415-1307
References
TAC MC5022
Download: ML050870298 (5)

Text

March 30, 2005 Mr. Rick A. Muench President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation Post Office Box 411 Burlington, KS 66839

SUBJECT:

WOLF CREEK GENERATING STATION - REQUEST FOR ADDITIONAL INFORMATION RELATED TO THE STEAM GENERATOR TUBE INSPECTION

SUMMARY

REPORTS FOR THE FALL 2003 OUTAGE (TAC NO. MC5022)

Dear Mr. Muench:

By letters dated November 10, 2003 (WO 03-0063), and October 27, 2004 (WM 04-0046), Wolf Creek Nuclear Operating Corporation submitted the steam generator tube inspection summary reports for the fall 2003 outage at Wolf Creek Generating Station (WCGS), in accordance with the Technical Specifications. These summary reports did not submit any request to change the WCGS operating license.

Enclosed is a request for additional information (RAI), which is needed by the Nuclear Regulatory Commission (NRC) staff to complete its review of these summary reports. The RAI has been discussed with your staff and they have agreed to submit the information in the RAI by July 15, 2005. Any changes to the attached RAI, related to the questions sent to your staff by email, were editorial in nature. Submitting the information by the above date will assist the NRC staff in completing its review by October 2005.

Sincerely,

/RA/

Jack Donohew, Senior Project Manager, Section 2 Project Directorate IV Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-483

Enclosure:

Request for Additional Information cc w/encl: See next page

Mr. Rick A. Muench March 30, 2005 President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation Post Office Box 411 Burlington, KS 66839

SUBJECT:

WOLF CREEK GENERATING STATION - REQUEST FOR ADDITIONAL INFORMATION RELATED TO THE STEAM GENERATOR TUBE INSPECTION

SUMMARY

REPORTS FOR THE FALL 2003 OUTAGE (TAC NO. MC5022)

Dear Mr. Muench:

By letters dated November 10, 2003 (WO 03-0063), and October 27, 2004 (WM 04-0046), Wolf Creek Nuclear Operating Corporation submitted the steam generator tube inspection summary reports for the fall 2003 outage at Wolf Creek Generating Station (WCGS), in accordance with the Technical Specifications. These summary reports did not submit any request to change the WCGS operating license.

Enclosed is a request for additional information (RAI), which is needed by the Nuclear Regulatory Commission (NRC) staff to complete its review of these summary reports. The RAI has been discussed with your staff and they have agreed to submit the information in the RAI by July 15, 2005. Any changes to the attached RAI, related to the questions sent to your staff by email, were editorial in nature. Submitting the information by the above date will assist the NRC staff in completing its review by October 2005.

Sincerely,

/RA/

Jack Donohew, Senior Project Manager, Section 2 Project Directorate IV Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-483 DISTRIBUTION:

PUBLIC

Enclosure:

Request for Additional Information PDIV-2 Reading RidsNrrDlpmPdiv(HBerkow) cc w/encl: See next page RidsNrrDlpmPdiv2(RGramm)

RidsNrrPMJDonohew RidsNrrLALFeizollahi RidsOgcRp RidsACRSACNWMailCenter RidsRegion4MailCenter (D. Graves)

LLund YDiaz-Castillo ACCESSION NO.: ML050870298 NRR-088 OFFICE PDIV-2/PM PDIV-2/LA EMCB/SC PDIV-2/SC NAME JDonohew LFeizollahi LLund RGramm DATE 3 /30/05 3/29/05 03/02/05 3/30/05 OFFICIAL RECORD COPY

Wolf Creek Generating Station cc:

Jay Silberg, Esq. Vice President Operations/Plant Manager Shaw Pittman, LLP Wolf Creek Nuclear Operating Corporation 2300 N Street, NW P.O. Box 411 Washington, D.C. 20037 Burlington, KS 66839 Regional Administrator, Region IV Supervisor Licensing U.S. Nuclear Regulatory Commission Wolf Creek Nuclear Operating Corporation 611 Ryan Plaza Drive, Suite 400 P.O. Box 411 Arlington, TX 76011-7005 Burlington, KS 66839 Senior Resident Inspector U.S. Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Resident Inspectors Office/Callaway Plant P.O. Box 311 8201 NRC Road Burlington, KS 66839 Steedman, MO 65077-1032 Chief Engineer, Utilities Division Kansas Corporation Commission 1500 SW Arrowhead Road Topeka, KS 66604-4027 Office of the Governor State of Kansas Topeka, KS 66612 Attorney General 120 S.W. 10th Avenue, 2nd Floor Topeka, KS 66612-1597 County Clerk Coffey County Courthouse 110 South 6th Street Burlington, KS 66839 Vick L. Cooper, Chief Air Operating Permit and Compliance Section Kansas Department of Health and Environment Bureau of Air and Radiation 1000 SW Jackson, Suite 310 Topeka, KS 66612-1366

REQUEST FOR ADDITIONAL INFORMATION RELATED TO STEAM GENERATOR TUBE INSPECTION

SUMMARY

REPORTS WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION DOCKET NO. 50-482 By letters dated November 10, 2003, and October 27, 2004, Wolf Creek Nuclear Operating Corporation (the licensee) submitted the steam generator tube inspection summary reports for the fall 2003 outage at Wolf Creek Generating Station, in accordance with the Technical Specifications. Based on its review of the summary reports, the Nuclear Regulatory Commission (NRC) staff requests the following additional information:

1. Describe what actions, if any, were taken to verify that the steam generator tubes were manufactured (i.e., processing, heat treatment, etc.) as specified so as to exhibit optimal resistance to degradation (refer to NRC Information Notice 2002-21, Supplement 1, dated April 1, 2003). If tubes with non-optimal tube processing were identified, discuss the results of the inspections performed on these tubes.

2. On page one of its November 10, 2003 report, the licensee indicated that one damaged mechanical plug in steam generator D was replaced with a welded plug. Discuss what caused the damage to this mechanical plug and the extent of the damage, including if the plug was replaced for a reason other than inadequate structural integrity for plant restart from the outage (e.g., because of future inspection concerns, long-term cracking concerns, expected reduction in structural integrity during next operating cycle, etc.). If the plug was replaced because of inadequate structural integrity, discuss the implications this could have on the rest of the plugs in the steam generator.

3. On page two of its October 27, 2004 report, the licensee indicated that six possible loose parts indications were identified in steam generator A and four, in steam generator D. With respect to these indications, discuss the following:

a. Was there any wear associated with the loose part indications or were these signals just indications that a loose part may be present.

b. Was a visual inspection performed at these locations.

c. Was a foreign object search and retrieval performed and were any loose parts removed from the steam generators. If any loose parts were not removed, address whether an assessment was made of the impact that the loose parts could have on tube integrity during the interval between tube inspections.

4. On page two of the inservice inspection report submitted by letter dated October 27, 2004, the licensee indicated that two permeability variation indications were identified in steam generator A and three, in steam generator D. Because permeability variations can affect the ability to effectively assess the condition of the tube, discuss whether the tubes with the permeability variation indications were plugged or left in service. In addition, discuss whether these signals were of sufficient magnitude to effectively assess the condition of the tube. If the tubes were not plugged and the permeability variations affected the ability to assess the condition of the tubes, discuss the basis for leaving them in service.

5. On page two of its October 27, 2004 report, the licensee indicated that one volumetric indication was identified in steam generator A and five, in steam generator D. Discuss if these indications are the same as (1) the top of the tubesheet indications, and (2) the indication found near the fifth support plate on the hot leg side of steam generator D. If they are not, discuss the nature and cause of these indications.

6. On page 32 of its October 27, 2004 report, the licensee addressed four tubes with volumetric indications. The licensee judged these indications to be a result of wear with previous foreign objects or due to manufacturing anomalies. With respect to these indications, address the following:

a. Did the indications initiate from the inside or outside diameter of the tube.

b. Depending on whether the indications are initiated from either the inside or outside diameter of the tube, discuss the cause of these indications (e.g., previous loose parts or manufacturing anomalies). If the indications are initiated from the outside diameter, are located below the top of the tubesheet, and attributed to loose parts, discuss how the damage is postulated to have occurred. If the indications are in the interior of the bundle and are attributed to loose parts, discuss whether any loose parts were found in the vicinity of these tubes. In addition, discuss how it was confirmed that the indications were not caused by some other mechanism (e.g., inter-granular attack).

c. If the indications are attributed to manufacturing anomalies, discuss past inspection results of these tubes.

d. Given that some indications are located in the interior of the tube bundle, and this location is an unusual location for a loose part, discuss any theories and conclusions regarding the cause of the loose parts.