ML080030178

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Review of Steam Generator Tube Inservice Inspection Report for 2006 Refueling Outage
ML080030178
Person / Time
Site: Kewaunee Dominion icon.png
Issue date: 01/15/2008
From: Milano P
NRC/NRR/ADRO/DORL/LPLIII-1
To: Christian D
Dominion Energy Kewaunee
Milano P, NRR/DORL/LPLIII-1, 415-1457
References
TAC MC5226
Download: ML080030178 (5)


Text

January 15, 2008 Mr. David A. Christian Senior Vice President and Chief Nuclear Officer Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711

SUBJECT:

KEWAUNEE POWER STATION - REVIEW OF STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT FOR 2006 REFUELING OUTAGE (TAC NO. MC5226)

Dear Mr. Christian:

In a letter dated March 29, 2007, Dominion Energy Kewaunee, Inc. (DEK) submitted the steam generator (SG) tube inspection report for the 2006 refueling outage at Kewaunee Power Station, in accordance with Technical Specification (TS) Section 6.9.b.4, Steam Generator Tube Inspection Report. By letter dated September 13, 2007, DEK provided additional information regarding this report in response to request to questions from the Nuclear Regulatory Commission (NRC) staff on August 9, 2007.

The NRC staff has completed its review of the SG tube inspection report for the 2006 outage, and concludes that DEK has provided the information required by the TSs and that no additional followup is required at this time. The NRC staffs review of the report is enclosed.

Sincerely,

/RA/

Patrick D. Milano, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-305

Enclosure:

As stated cc: See next page

ML080030178 OFFICE LPL3-1/PM LPL3-1/LA DCI/CSGB/BC LPL3-1/(A)BC NAME PMilano THarris AHiser CMunson DATE 01/4/08 01/4/08 01/10/08 01/15/08 Kewaunee Power Station cc:

Resident Inspectors Office U.S. Nuclear Regulatory Commission N490 Hwy 42 Kewaunee, WI 54216-9510 Regional Administrator, Region III U.S. Nuclear Regulatory Commission Suite 210 2443 Warrenville Road Lisle, IL 60532-4351 Ms. Leslie N. Hartz Dominion Energy Kewaunee, Inc.

Kewaunee Power Station N 490 Highway 42 Kewaunee, WI 54216 Mr. Chris L. Funderburk Director, Nuclear Licensing and Operations Support Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. Thomas L. Breene Dominon Energy Kewaunee, Inc.

Kewaunee Power Station N490 Highway 42 Kewaunee, WI 54216 Ms. Lillian M. Cuoco, Esq.

Senior Counsel Dominion Resources Services, Inc.

Millstone Power Station Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385

SUMMARY

OF NUCLEAR REGULATORY COMMISSION STAFF REVIEW STEAM GENERATOR TUBE INSERVICE INSPECTION REPORTS FOR THE 2006 REFUELING OUTAGE KEWAUNEE POWER STATION DOCKET NO. 50-305 By letter dated January 10, 2007 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML070100524), Dominion Energy Kewaunee, Inc (the licensee) submitted its summary report of the inservice inspection (ISI) required by Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code for the Kewaunee Power Station (KPS). The ISI was performed during the 2006 refueling outage (RFO), which took place from September 2 through October 26, 2006. This report in part, included a summary of the ISI performed for the tubing in steam generators (SGs) 1A and 1B in accordance with Technical Specification (TS) 6.22, Steam Generator (SG) Program. As required by TS 6.9.b.4, Steam Generator Tube Inspection Report, a report must be submitted within 180 days after the initial entry into intermediate shutdown following completion of an inspection performed in accordance with TS 6.22. By letter dated March 29, 2007 (ADAMS No.

ML071020161), the licensee submitted its SG Tube Inspection Report for the 2006 RFO.

In a letter dated September 13, 2007 (ADAMS No. ML072680850), the licensee responded to a Nuclear Regulatory Commission (NRC) staff request for additional information dated August 9, 2007 (ADAMS No. ML072190202), regarding the SG tube inspections in the 2006 RFO.

In 2001, the licensee replaced portions of each of its Westinghouse Model 51 SGs with the Westinghouse Model 54F replacement SG complete lower assembly and modified upper assembly. The replacement lower assemblies contain 3592 thermally-treated Alloy 690 tubes.

Each tube has a nominal outside diameter of 0.875-inch, and a nominal wall thickness of 0.050-inch. The tubes were hydraulically expanded into the tubesheet and the Type 405 stainless steel tube support plates contain broached quatrefoil holes.

The fall 2006 inspection marked the second ISI since the SG lower assembly replacement. At the time of this inspection, the SGs had accumulated approximately 33 effective full power months of operation since the first ISI of the tubes. This is within the first half of the 144 effective full power month inspection period, as described in TS 6.22.d.2.

The licensee provided the scope, extent, methods, and results of its SG tube inspections in the documents referenced above. In addition, the licensee reported that no tubes were preventatively plugged and no degradation was found.

ENCLOSURE

After the review of the information provided by the licensee, the NRC staff has the following comment/observation:

The upper internal and mid-deck regions of the steam drum were inspected during the 2006 outage in both SGs. No foreign objects were observed in the steam drums of either SG; however, several disruptions in the magnetite layer were observed on the primary moisture separator riser barrel in the area of the J-nozzles. The disruptions were darker in appearance but not reflective. This indicated to the licensee that the surface was not completely stripped of magnetite.

Based on its review, the NRC staff concludes that the licensee provided the information required by the TSs and that at this time no additional information is required. In general, the SG tube inspections at KPS appear to be consistent with the objective of detecting potential tube degradation and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.