ML12146A107

Vermont Yankee Nuclear Power Station - Supplemental Information Request on Steam Dryer Inspection (TAC ME7733)

ML12146A107
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	01/30/2012
From:	Kim J S Plant Licensing Branch 1
To:	DeVincentis J M Entergy Nuclear Operations
References
TAC ME7733
Download: ML12146A107 (3)

Text

Kim, JamesFrom:Sent:To:Cc:Subject:Attachments:Importance:Kim, JamesMonday, January 30, 2012 11:14 AM'Devincentis, James MCouture III, Philip'Acceptance Review--Vermont Yankee steam dryer Inspections---TAC#ME7733Vermont Yankee steam dryer.docxHighJim D.Attached is the supplemental info. requested by the tech. staff to make the amendment request acceptable forreview. Please let me know if you would like to set up a phone call to discuss it.ThanksJim KimI Request for Supplemental InformationVermont Yankee License Amendment RequestLicense Condition Change Regarding Steam Dryer Monitoring and InspectionTAC No. ME7733By letter dated December 22, 2011, Entergy Nuclear Operations Inc. (Entergy or the licensee)submitted a license condition change requesting the usage of the inspection requirementsallowed by the BWRVIP-139-A topical report (TR), "BWR Vessel and Internals Project SteamDryer Inspections and Flaw Evaluation Guidelines," at Vermont Yankee (VY) nuclear powerplant. In the technical evaluation section of its submittal, the licensee stated that the steamdryer was inspected during previous refueling outages and these inspections did not identify anyunacceptable fatigue induced structural flaws. Consistent with the requirements addressed inSection 5.3.4 of the BWRVI P-1 39-A, the licensee's proposed change includes adoption of there-inspection frequency of the steam dryer at every seven refueling outages based on 18 monthcycle.In accordance with the criteria of Section 3.1.2 of Appendix B in NRR Office Instruction, LIC-109, "Guide for Performing Acceptance Reviews -Technical Staff Criteria," the NRC staff isunable to determine whether the guidance of BWRVIP-1 39-A cited in the requested licensingaction (RLA) is being used in accordance with the limitations and conditions imposed by theNRC staff in the Safety Evaluation (SE) accompanying the aforementioned TR. Thisdetermination is based on insufficiencies identified in the December 22, 2011, submittal, whichare detailed below. However, based on the previous inspection results cited by the licensee inthe RLA, the supplemental information necessary for the NRC staff to review the RLA appearsreadily available to the licensee. Therefore, the NRC staff considers the RLA "unacceptable forreview with opportunity to supplement," in accordance with LIC-109.As indicated in Section 5.3.4 of the BWRVIP-139-A, "Re-inspection Recommendations,"licensees must justify any adjustments to steam dryer inspection programs when commitmentsexist to implement the re-inspection provisions of GE Services Information Letter (SIL) No. 44,"BWR steam dryer integrity." Accordingly, the NRC staff requests that the licensee submit arobust technical justification that demonstrates that the existing flaws would not cause anydetrimental effect on the functionality and the structural integrity of the steam dryer. Thisjustification shall encapsulate the following information which is to be derived from theconsecutive inspections conducted during the 2007, 2008 and 2010 refueling outages:(1) Length of the indications-average length of the flaws/relevant indications;(2) Distribution of indication per unit area-random, concentrated at high stresslocations, at the heat affected zone (HAZ);(3) Characterization of the relevant indications/flaws,(4) Engineering disposition of the relevant indications (> 1/16") based on the loadingconditions, (5) Locations of cracks i.e., fatigue cracks and/or IGSCC and maximum length of thecracks.The expectations are that the licensee should demonstrate that compliance with therequirements (i.e., the re-inspection frequency at every seven refueling outages based on 18month cycle ) addressed in the BWRVIP-139-A report is adequate to maintain the functionalityand structural integrity of the steam dryer. The staff requires that this justification be submittedas part of the proposed change in the licensing condition, and if the licensee cannot fulfill thisrequirement, the staff may deny the proposed change.