ML102650013

Acceptance Review E-mail, Relief Request RR-12, from Requirements of ASME Code Case N-722 Visual Examination of Reactor Vessel Hot-Leg Nozzle to Safe End Dissimilar Metal Welds for 4th 10-Year Inservice Inspection Interval (ME4541)

ML102650013
Person / Time
Site:	Fort Calhoun
Issue date:	09/21/2010
From:	Lynnea Wilkins Plant Licensing Branch IV
To:	Hansher B Omaha Public Power District
Wilkins, L E, NRR/DORL/LPL4, 415-1377
References
TAC ME4541
Download: ML102650013 (1)

Text

From: Wilkins, Lynnea Sent: Tuesday, September 21, 2010 4:54 PM To: HANSHER, BILL R Cc: Burkhardt, Janet; Lent, Susan; Markley, Michael; Collins, Jay; Lupold, Timothy

Subject:

ME4541 - Acceptance of FCS Request for Relief from Code Case N-722 Visual Examination of the Reactor Vessel Hot Leg Nozzle to Safe End Dissimilar Metal Welds

Bill, By letter dated August 16, 2010, Omaha Public Power District submitted a Request for Relief from Code Case N-722 Visual Examination (VE) of the Reactor Vessel Hot Leg Nozzle to Safe End Dissimilar Metal Welds for the Fort Calhoun Station, Unit No. 1 (FCS). The relief request proposes an alternative to the American Society of Mechanical Engineers (ASME), Code Section XI, Code Case N-722 VE requirements. Specifically, OPPD proposes to credit (1) augmented examinations performed during previous refueling outages, (2) deterministic analyses of crack growth with positive results, and (3) the addition of zinc to the reactor coolant system to mitigate primary water stress corrosion cracking in lieu of the VE required by Code Case N-722.

The purpose of this letter is to provide the results of the NRC staff's acceptance review of this relief request. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review.

The acceptance review is also intended to identify whether the application has any readily apparent information insufficiencies in its characterization of the regulatory requirements or the licensing basis of the plant.

Pursuant to Sections 50.55a(a)(3)(i) and 50.55a(a)(3)(ii) of Title 10 of the Code of Federal Regulations (10 CFR), the applicant shall demonstrate that the proposed alternatives would provide an acceptable level of quality and safety, or that compliance with the specified requirements of Section 50.55a would result in hardship or unusual difficulty without a compensating increase in the level of quality or safety.

The NRC staff has reviewed your application and concluded that it does provide technical information in sufficient detail to enable the staff to proceed with its detailed technical review and make an independent assessment regarding the acceptability of the proposed amendment in terms of regulatory requirements and the protection of public health and safety and the environment. Please note, the NRC staff has determined a need for substantive requests for additional information (RAIs) to complete the technical review. You will be advised of these RAIs by separate correspondence.

If you have any questions, please contact the me.

Lynnea Wilkins, Project Manager Fort Calhoun Station, Unit 1 Cooper Nuclear Station Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation US Nuclear Regulatory Commission

Phone: 301-415-1377 E-mail Properties Mail Envelope Properties (F371D08C516DE74F81193E6D891DC4AF3874D23FFA)

Subject:

ME4541 - Acceptance of FCS Request for Relief from Code Case N-722 Visual Examination of the Reactor Vessel Hot Leg Nozzle to Safe End Dissimilar Metal Welds Sent Date: 9/21/2010 4:54:30 PM Received Date: 9/21/2010 4:54:30 PM From: Wilkins, Lynnea Created By: Lynnea.Wilkins@nrc.gov Recipients:

bhansher@oppd.com (HANSHER, BILL R)

Tracking Status: None Janet.Burkhardt@nrc.gov (Burkhardt, Janet)

Tracking Status: None Susan.Lent@nrc.gov (Lent, Susan)

Tracking Status: None Michael.Markley@nrc.gov (Markley, Michael)

Tracking Status: None Jay.Collins@nrc.gov (Collins, Jay)

Tracking Status: None Timothy.Lupold@nrc.gov (Lupold, Timothy)

Tracking Status: None Post Office:

HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 12793 9/21/2010 Options Expiration Date:

Priority: olImportanceNormal ReplyRequested: True Return Notification: False Sensitivity: olNormal Recipients received: