ML073200204

Request for Additional Information on Two Steam Generator Inspection Reports

ML073200204
Person / Time
Site:	Cook
Issue date:	12/13/2007
From:	Tam P NRC/NRR/ADRO/DORL/LPLIII-1
To:	Rencheck M Indiana Michigan Power Co
tam P, NRR/DORL, 415-1451
References
TAC MD5944, TAC MD5945
Download: ML073200204 (4)

Text

December 13, 2007 Mr. Michael W. Rencheck Senior Vice President and Chief Nuclear Officer Indiana Michigan Power Company Nuclear Generation Group One Cook Place Bridgman, MI 49106

SUBJECT:

D. C. COOK NUCLEAR PLANT, UNIT 1 (DCCNP-1) - REQUEST FOR ADDITIONAL INFORMATION ON TWO STEAM GENERATOR INSPECTION REPORTS (TAC NOS. MD5944 AND MD5945)

Dear Mr. Rencheck:

By letters dated October 31, 2006, and February 27, 2007, Indiana Michigan Power Company submitted information pertaining to the 2006 steam generator tube inspections at DCCNP-1 and other things. The Nuclear Regulatory Commission (NRC) staff reviewed the information transmitted by those letters and has generated draft questions, which had been e-mailed to your staff (Accession No. ML072851201) on October 12, 2007. The NRC staff discussed the draft questions with your staff in a telephone conference on November 13, 2007. As a result of that discussion and subsequent internal deliberation, the NRC staff revised draft Question 2. The NRC staff reviewed the information in the Inspection Report (IR) dated February 12, 2007, and determined that more information is needed than what is provided in the IR. Accordingly, the NRC staff has finalized the enclosed Request for Additional Information (RAI).

Please respond within 30 days of the date of this letter. Feel free to contact me if you need clarification of this RAI.

Sincerely,

/RA/

Peter S. Tam, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-315 and 50-316

Enclosure:

As stated cc: See next page

ML073200204 OFFICE LPL3-1\PM LPL3-1/LA CSGB/BC LPL3-1/BC(A)

NAME PTam THarris AHiser CMunson DATE 12/7/07 12/7/07 12/ 12 /07 12/ 13 /07 REQUEST FOR ADDITIONAL INFORMATION D.C. COOK NUCLEAR PLANT, UNIT 1 STEAM GENERATOR TUBE INSPECTIONS PERFORMED IN 2006 (1) Please discuss the root cause of the tube plugging error in 2002 in Steam Generator (SG) 14.

(2) In your February 27, 2007 letter, you indicated that, based upon the results from the 2006 (SG) tube inspections, the SGs remain on a maximum inspection interval of 40 calendar months. As a result, you indicated that your next scheduled inservice inspection is in the fall of 2009. Subsequent to the issuance of this letter, your SG technical specification (TS) requirements were modified. These new requirements specify different maximum inspection intervals that are based on effective full power months of operation. In addition, they specify a different inspection scope. As a result, please verify that if your next SG tube inspection is conducted in the fall of 2009, that you will satisfy your current SG TS requirements. Please include the following in this response: for each refueling outage or SG inspection outage since replacement of your SGs, the cumulative effective full power months (or years) of operation that the SGs had accumulated at the time of the outage.

(3) Please discuss whether the wear indications in the tubes in row 69 column 29 (R69C29),

R69C27, and R68C28 were detected with the bobbin coil. Please discuss whether the possible loose part (PLP) indications in R84C60 and R85C61 were identified with the bobbin coil. Please clarify which five tubes had PLP indications in SG 13. If the above indications were not detected with the bobbin coil, please discuss the basis for the rotating probe inspection scope at the top of the tubesheet. In this response, discuss the scope and results of any secondary side inspections (including foreign object search and retrieval).

(4) You indicated that the tubesheet thickness is 21.25 inches and is clad on the primary side. Please clarify the thickness of the tubesheet with and without the cladding.

Donald C. Cook Nuclear Plant, Units 1 and 2 cc:

Attorney General Michigan Department of Environmental Department of Attorney General Quality 525 West Ottawa Street Waste and Hazardous Materials Div.

Lansing, MI 48913 Hazardous Waste & Radiological Protection Section Township Supervisor Nuclear Facilities Unit Lake Township Hall Constitution Hall, Lower-Level North P.O. Box 818 525 West Allegan Street Bridgman, MI 49106 P. O. Box 30241 Lansing, MI 48909-7741 U.S. Nuclear Regulatory Commission Resident Inspector's Office Lawrence J. Weber, Plant Manager 7700 Red Arrow Highway Indiana Michigan Power Company Stevensville, MI 49127 Nuclear Generation Group One Cook Place Kimberly Harshaw, Esquire Bridgman, MI 49106 Indiana Michigan Power Company One Cook Place Joseph Jensen, Site Vice President Bridgman, MI 49106 Indiana Michigan Power Company Nuclear Generation Group Mayor, City of Bridgman One Cook Place P.O. Box 366 Bridgman, MI 49106 Bridgman, MI 49106 Special Assistant to the Governor Room 1 - State Capitol Lansing, MI 48909 Susan D. Simpson Regulatory Affairs Manager Indiana Michigan Power Company Nuclear Generation Group One Cook Place Bridgman, MI 49106