ML063420033

Correction of Safety Evaluation Associated with Authorization of an Alternative

ML063420033
Person / Time
Site:	Cook
Issue date:	12/29/2006
From:	Tam P NRC/NRR/ADRO/DORL/LPLIII-1
To:	Nazar M Indiana Michigan Power Co
References
TAC MC8569, TAC MC8570
Download: ML063420033 (4)

Text

December 29, 2006 Mr. Mano K. Nazar Senior Vice President and Chief Nuclear Officer Indiana Michigan Power Company Nuclear Generation Group One Cook Place Bridgman, MI 49106

SUBJECT:

DONALD C. COOK NUCLEAR PLANT, UNITS 1 AND 2 - CORRECTION OF SAFETY EVALUATION RE. RELIEF REQUEST ISIR-19 REGARDING CLASS 1 AND 2 PIPING WELD INSPECTION REQUIREMENTS (TAC NOS. MC8569 AND MC8570)

Dear Mr. Nazar:

By letter dated May 31, 2006, the Nuclear Regulatory Commission (NRC) staff authorized an alternative from certain examination requirements in the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, for Class 1 and 2 piping welds during the third 10-year inservice inspection interval.

By letter dated July 28, 2006, Mr. Joseph N. Jensen of Indiana Michigan Power Company informed the NRC that the safety evaluation (SE) enclosed with the NRCs May 31, 2006, letter, could be read in a way not intended by the NRC staff. The NRC staff agrees with his observation and is, thus, re-issuing Page 5 of the SE. The revised Page 5 (enclosed), has deleted the phrase by 6 months prior to the first outage of the third period in the last sentence of the third paragraph. This revision of Page 5 eliminates the possible misinterpretation but does not change the conclusion of the SE. If you have any questions, please call me at 301-415-1451.

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 w/encl: See next page

ML063420033 OFFICE NRR/LPL3-1/PM NRR/LPL3-1/LA NRR/CNPB NRR/CNPB/BC NRR/LPL3-1/BC NAME PTam THarris AKeim WKoo for TChan LRaghavan DATE 12/8/06 12/8/06 12/11/06 12/28/06 12/29/06 3.6 NRC Staff Evaluation The NRC staff has reviewed the information concerning the ISI program request for relief and the proposed alternative submitted by the licensee in letters referenced above for the second period of the third 10-year ISI program at DCCNP-1 and DCCNP-2. The Code requires that at least 50 percent of the welds in each category be examined during the second period.

Approximately 70 welds for Unit 1 and 44 welds for Unit 2 would need to be examined during the remaining outage of the second period.

NRC Information Notice (IN) 98-44, "Ten-Year Inservice Inspection (ISI) Program Update for Licensees that Intend to Implement Risk-Informed ISI of Piping," states that for licensees who intend to implement a RI-ISI program for piping and following the guidance provided in IN 98-44, the NRC staff will consider authorizing a delay of up to 2 years in implementation of the ISI program for piping only. The second period for DCCNP-1 will end January 31, 2007, and DCCNP-2 will end its second period on September 30, 2006. The third 10-year ISI interval for both units will end on February 28, 2007. The licensee intends to use the methodology in Code Case N-716 for both units' RI-ISI program. However, the NRC staff has not yet approved Code Case N-716. The Grand Gulf Nuclear Station is scheduled as the pilot plant for a RI-ISI program using Code Case N-716, and the NRC staff will make its determination regarding N-716 following its review of Grand Gulfs application to use the methodology. The Cook licensee committed in its December 28, 2005, letter to submit its RI-ISI program for NRC approval by July 31, 2006.

Typically, RI-ISI programs result in a significant reduction in the required number of piping weld examinations. Although the licensee will be performing examinations on fewer locations, the locations selected will be based on knowledge of potential degradation mechanisms and the use of effective examination requirements for the potential degradation mechanism at locations that have been determined to be highly safety significant. Examination of the reduced number of Class 1 and Class 2 piping welds would be performed over the outages in the third period of the third 10-year inspection interval, such that a minimum of 66 percent of the RI-ISI examinations would be completed. The licensees proposed RI-ISI program will be reviewed by the NRC and will require NRC approval prior to implementation. If the NRC staff does not approve the DCCNP-1 and DCCNP-2 RI-ISI program, the licensee will be required to complete l the remaining ASME Code-required piping examinations during the third period at each unit.

The goal of piping ISI is to detect precursors to possible future piping failure. By examining certain piping welds once every ten years, the licensee is monitoring to determine whether any degradation is occurring. Based on the number of required examinations performed during the current interval, the NRC staff believes that any significant active degradation would have been detected. Furthermore, the NRC staff believes a two-year delay of the requested percentage of pipe examinations would not provide sufficient time for specific degradation mechanisms to progress to failure. Therefore, the NRC staff concludes that the licensee's proposed alternative provides an acceptable level of quality and safety.

Corrected by letter of 12/29/06 l

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

Regional Administrator, Region III Michigan Department of Environmental U.S. Nuclear Regulatory Commission Quality Suite 210 Waste and Hazardous Materials Div.

2443 Warrenville Road Hazardous Waste & Radiological Lisle, IL 60532-4351 Protection Section Nuclear Facilities Unit Attorney General Constitution Hall, Lower-Level North Department of Attorney General 525 West Allegan Street 525 West Ottawa Street P. O. Box 30241 Lansing, MI 48913 Lansing, MI 48909-7741 Township Supervisor Lawrence J. Weber, Plant Manager Lake Township Hall Indiana Michigan Power Company P.O. Box 818 Nuclear Generation Group Bridgman, MI 49106 One Cook Place Bridgman, MI 49106 U.S. Nuclear Regulatory Commission Resident Inspector's Office Mark A. Peifer, Site Vice President 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 Bridgman, MI 49106 Mayor, City of Bridgman P.O. Box 366 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